What is the current concentration of PM10 in San Mateo, California?

The current PM10 concentration at San Mateo, California is 48.986 μg/m3.

What is the current concentration of sulfur dioxide (SO2) in San Mateo, California?

The current sulfur dioxide (SO2) concentration at San Mateo, California is 0.445 ppb.

What is the current concentration of ozone (O3) in San Mateo, California?

The current ozone (O3) concentration at San Mateo, California is 8.509 ppm.

What is the current concentration of nitrogen dioxide (NO2) in San Mateo, California?

The current nitrogen dioxide (NO2) concentration at San Mateo, California is 10.965 ppb.

San Mateo, California live air quality index now

Q: What is the current concentration of PM2.5 in San Mateo, California?

The current PM2.5 concentration at San Mateo, California is 12.552 μg/m3.

Stay updated with real-time air quality in San Mateo, California featuring accurate data on AQI, PM_2.5, PM₁₀, O₃, NO₂, SO₂, and CO levels. Use our interactive map and detailed forecasts to monitor pollution trends, manage health risks, and plan your daily activities with confidence.

Live AQI (Air Quality Index)

Moderate

San Mateo, California

Last updated: ... (Local time)

Major air pollutants in San Mateo, California

Good

Fine

Moderate

Poor

Very poor

Hazardous

Particulate Matter_2.5 (PM_2.5)

12.55 μg/m³

12.1

35.5

55.5

250.5

500.5+

Particulate Matter₁₀ (PM₁₀)

48.99 μg/m³

155

255

425

605+

Ozone (O₃)

8.51 ppb

201

201+

Sulfur Dioxide (SO₂)

0.45 ppb

186

605

1005+

Nitrogen Dioxide (NO₂)

10.96 ppb

101

361

1250

2050+

Carbon Monoxide (CO)

0.45 ppm

4.5

9.5

12.5

230.5

50.5+

Pollen Level

Low

San Mateo, California

Get Live Pollen Counts

San Mateo, California

Scroll To Air Quality Map

Track live San Mateo, California air quality forecast and history

Time	AQI	PM_2.5	PM₁₀	O₃	SO₂	NO₂	CO
2025-12-05T15:00:00.000Z	56 \| moderate	12.468 \| fine	50.135 \| good	6.351 \| good	0.455 \| good	19.703 \| good	0.615 \| good
2025-12-05T16:00:00.000Z	56 \| moderate	12.323 \| fine	45.957 \| good	5.487 \| good	0.438 \| good	15.389 \| good	0.81 \| good
2025-12-05T17:00:00.000Z	64 \| moderate	16.404 \| fine	71.346 \| fine	5.575 \| good	0.419 \| good	15.004 \| good	0.755 \| good
2025-12-05T18:00:00.000Z	62 \| moderate	15.393 \| fine	60.739 \| fine	10.778 \| good	0.464 \| good	11.911 \| good	0.607 \| good
2025-12-05T19:00:00.000Z	66 \| moderate	17.207 \| fine	71.549 \| fine	10.688 \| good	0.484 \| good	11.23 \| good	0.428 \| good
2025-12-05T20:00:00.000Z	69 \| moderate	19.026 \| fine	46.858 \| good	12.843 \| good	0.434 \| good	11.497 \| good	0.342 \| good
2025-12-05T21:00:00.000Z	67 \| moderate	18.162 \| fine	27.122 \| good	13.246 \| good	0.411 \| good	10.06 \| good	0.328 \| good
2025-12-05T22:00:00.000Z	66 \| moderate	16.771 \| fine	41.297 \| good	14.676 \| good	0.533 \| good	11 \| good	0.27 \| good
2025-12-05T23:00:00.000Z	73 \| moderate	20.881 \| fine	43.581 \| good	13.259 \| good	0.499 \| good	8.376 \| good	0.274 \| good
2025-12-06T00:00:00.000Z	64 \| moderate	16.213 \| fine	79.249 \| fine	12.999 \| good	0.485 \| good	11.164 \| good	0.256 \| good
2025-12-06T01:00:00.000Z	66 \| moderate	16.687 \| fine	74.624 \| fine	15.116 \| good	0.441 \| good	12.38 \| good	0.26 \| good
2025-12-06T02:00:00.000Z	67 \| moderate	18.219 \| fine	69.407 \| fine	12.789 \| good	0.369 \| good	14.866 \| good	0.306 \| good
2025-12-06T03:00:00.000Z	67 \| moderate	18.264 \| fine	76.721 \| fine	9.994 \| good	0.337 \| good	16.48 \| good	0.404 \| good
2025-12-06T04:00:00.000Z	69 \| moderate	19.494 \| fine	76.884 \| fine	10.957 \| good	0.35 \| good	16.035 \| good	0.479 \| good
2025-12-06T05:00:00.000Z	67 \| moderate	17.359 \| fine	88.212 \| fine	14.344 \| good	0.433 \| good	14.904 \| good	0.48 \| good
2025-12-06T06:00:00.000Z	66 \| moderate	16.583 \| fine	81.024 \| fine	12.833 \| good	0.399 \| good	11.799 \| good	0.541 \| good
2025-12-06T07:00:00.000Z	71 \| moderate	19.696 \| fine	75.612 \| fine	13.8 \| good	0.415 \| good	13.895 \| good	0.512 \| good
2025-12-06T08:00:00.000Z	71 \| moderate	19.891 \| fine	48.533 \| good	13.656 \| good	0.384 \| good	12.246 \| good	0.375 \| good
2025-12-06T09:00:00.000Z	71 \| moderate	20.121 \| fine	71.67 \| fine	14.093 \| good	0.404 \| good	12.3 \| good	0.376 \| good
2025-12-06T10:00:00.000Z	75 \| moderate	21.682 \| fine	97.576 \| fine	10.242 \| good	0.932 \| good	11.181 \| good	0.43 \| good
2025-12-06T11:00:00.000Z	56 \| moderate	12.38 \| fine	52.997 \| good	4.873 \| good	0.86 \| good	7.401 \| good	0.382 \| good
2025-12-06T12:00:00.000Z	68 \| moderate	14.592 \| fine	88.617 \| fine	5.027 \| good	0.316 \| good	8.184 \| good	0.371 \| good
2025-12-06T13:00:00.000Z	60 \| moderate	14.182 \| fine	60.734 \| fine	6.109 \| good	0.365 \| good	11.484 \| good	0.303 \| good
2025-12-06T14:00:00.000Z	58 \| moderate	13.436 \| fine	36.202 \| good	5.298 \| good	0.523 \| good	10.995 \| good	0.205 \| good
2025-12-06T15:00:00.000Z	64 \| moderate	15.661 \| fine	54.967 \| good	6.872 \| good	0.406 \| good	9.291 \| good	0.262 \| good
2025-12-06T16:00:00.000Z	64 \| moderate	15.652 \| fine	75.251 \| fine	3.9 \| good	0.373 \| good	7.952 \| good	0.294 \| good
2025-12-06T17:00:00.000Z	64 \| moderate	16.277 \| fine	72.902 \| fine	6.226 \| good	0.426 \| good	7.081 \| good	0.259 \| good
2025-12-06T18:00:00.000Z	64 \| moderate	16.33 \| fine	57.323 \| fine	8.067 \| good	0.516 \| good	6.653 \| good	0.297 \| good
2025-12-06T19:00:00.000Z	73 \| moderate	21.237 \| fine	96.446 \| fine	8.549 \| good	0.578 \| good	5.602 \| good	0.35 \| good
2025-12-06T20:00:00.000Z	73 \| moderate	21.275 \| fine	71.757 \| fine	8.831 \| good	0.558 \| good	6.521 \| good	0.332 \| good
2025-12-06T21:00:00.000Z	75 \| moderate	21.828 \| fine	51.58 \| good	9.852 \| good	0.572 \| good	7.384 \| good	0.351 \| good
2025-12-06T22:00:00.000Z	75 \| moderate	22.159 \| fine	93.756 \| fine	10.986 \| good	0.579 \| good	7.31 \| good	0.332 \| good
2025-12-06T23:00:00.000Z	71 \| moderate	19.539 \| fine	65.879 \| fine	10.278 \| good	0.493 \| good	6.905 \| good	0.298 \| good
2025-12-07T00:00:00.000Z	66 \| moderate	16.528 \| fine	73.694 \| fine	12.283 \| good	0.514 \| good	7.328 \| good	0.298 \| good
2025-12-07T01:00:00.000Z	64 \| moderate	15.7 \| fine	69.21 \| fine	13.064 \| good	0.444 \| good	9.51 \| good	0.319 \| good
2025-12-07T02:00:00.000Z	69 \| moderate	19.074 \| fine	58.927 \| fine	11.453 \| good	0.39 \| good	9.986 \| good	0.353 \| good
2025-12-07T03:00:00.000Z	60 \| moderate	14.079 \| fine	41.872 \| good	8.985 \| good	0.329 \| good	12.144 \| good	0.379 \| good
2025-12-07T04:00:00.000Z	56 \| moderate	11.955 \| good	32.778 \| good	13.396 \| good	0.318 \| good	12.044 \| good	0.502 \| good
2025-12-07T05:00:00.000Z	60 \| moderate	14.079 \| fine	24.015 \| good	9.842 \| good	0.278 \| good	10.168 \| good	0.545 \| good
2025-12-07T06:00:00.000Z	56 \| moderate	11.946 \| good	47.771 \| good	6.505 \| good	0.269 \| good	8.972 \| good	0.545 \| good
2025-12-07T07:00:00.000Z	67 \| moderate	18.365 \| fine	66.302 \| fine	8.163 \| good	0.269 \| good	9.184 \| good	0.53 \| good
2025-12-07T08:00:00.000Z	64 \| moderate	16.272 \| fine	68.538 \| fine	6.329 \| good	0.273 \| good	9.243 \| good	0.559 \| good
2025-12-07T09:00:00.000Z	66 \| moderate	17.094 \| fine	68.09 \| fine	8.761 \| good	0.324 \| good	8.122 \| good	0.49 \| good
2025-12-07T10:00:00.000Z	77 \| moderate	22.59 \| fine	93.139 \| fine	8.236 \| good	0.476 \| good	4.145 \| good	0.267 \| good
2025-12-07T11:00:00.000Z	56 \| moderate	12.11 \| fine	39.242 \| good	9.659 \| good	0.504 \| good	3.408 \| good	0.256 \| good
2025-12-07T12:00:00.000Z	64 \| moderate	16.192 \| fine	61.364 \| fine	5.154 \| good	0.338 \| good	7.356 \| good	0.22 \| good
2025-12-07T13:00:00.000Z	71 \| moderate	19.52 \| fine	84.237 \| fine	7.911 \| good	0.362 \| good	11.667 \| good	0.308 \| good
2025-12-07T14:00:00.000Z	58 \| moderate	12.552 \| fine	48.986 \| good	8.509 \| good	0.445 \| good	10.965 \| good	0.45 \| good
2025-12-07T14:00:00.000Z	58 \| moderate	12.552 \| fine	48.986 \| good	8.509 \| good	0.445 \| good	10.965 \| good	0.45 \| good
2025-12-07T15:00:00.000Z	62 \| moderate	14.897 \| fine	66.909 \| fine	4.145 \| good	1.428 \| good	16.762 \| good	0.243 \| good
2025-12-07T16:00:00.000Z	62 \| moderate	14.731 \| fine	66.183 \| fine	5.247 \| good	1.595 \| good	15.638 \| good	0.248 \| good
2025-12-07T17:00:00.000Z	66 \| moderate	16.616 \| fine	73.807 \| fine	4.495 \| good	1.762 \| good	14.515 \| good	0.254 \| good
2025-12-07T18:00:00.000Z	71 \| moderate	19.633 \| fine	86.32 \| fine	4.336 \| good	1.929 \| good	13.392 \| good	0.259 \| good
2025-12-07T19:00:00.000Z	71 \| moderate	20.407 \| fine	90.225 \| fine	5.836 \| good	2.083 \| good	12.451 \| good	0.237 \| good
2025-12-07T20:00:00.000Z	71 \| moderate	20.141 \| fine	88.984 \| fine	6.196 \| good	2.236 \| good	11.51 \| good	0.215 \| good
2025-12-07T21:00:00.000Z	67 \| moderate	18.335 \| fine	80.753 \| fine	6.598 \| good	2.39 \| good	10.569 \| good	0.193 \| good
2025-12-07T22:00:00.000Z	62 \| moderate	15.196 \| fine	67.499 \| fine	8.52 \| good	2.24 \| good	11.478 \| good	0.186 \| good
2025-12-07T23:00:00.000Z	58 \| moderate	13.272 \| fine	59.287 \| fine	10.168 \| good	2.09 \| good	12.387 \| good	0.18 \| good
2025-12-08T00:00:00.000Z	54 \| moderate	11.151 \| good	49.734 \| good	11.23 \| good	1.94 \| good	13.296 \| good	0.174 \| good
2025-12-08T01:00:00.000Z	44 \| good	8.152 \| good	36.017 \| good	9.674 \| good	1.846 \| good	14.261 \| good	0.197 \| good
2025-12-08T02:00:00.000Z	38 \| good	7.442 \| good	32.914 \| good	7.5 \| good	1.753 \| good	15.226 \| good	0.221 \| good
2025-12-08T03:00:00.000Z	44 \| good	7.872 \| good	34.6 \| good	6.453 \| good	1.659 \| good	16.192 \| good	0.244 \| good
2025-12-08T04:00:00.000Z	33 \| good	6.445 \| good	28.384 \| good	5.649 \| good	1.771 \| good	16.052 \| good	0.25 \| good
2025-12-08T05:00:00.000Z	27 \| good	5.391 \| good	23.645 \| good	5.249 \| good	1.882 \| good	15.911 \| good	0.256 \| good
2025-12-08T06:00:00.000Z	16 \| good	3.498 \| good	14.979 \| good	3.475 \| good	1.994 \| good	15.771 \| good	0.262 \| good
2025-12-08T07:00:00.000Z	27 \| good	4.897 \| good	21.536 \| good	1.441 \| good	1.92 \| good	15.672 \| good	0.261 \| good
2025-12-08T08:00:00.000Z	49 \| good	8.526 \| good	37.804 \| good	2.284 \| good	1.846 \| good	15.573 \| good	0.26 \| good
2025-12-08T09:00:00.000Z	58 \| moderate	12.567 \| fine	55.956 \| fine	1.85 \| good	1.772 \| good	15.474 \| good	0.259 \| good
2025-12-08T10:00:00.000Z	58 \| moderate	12.96 \| fine	58.351 \| fine	1.537 \| good	1.7 \| good	14.92 \| good	0.256 \| good
2025-12-08T11:00:00.000Z	60 \| moderate	14.399 \| fine	64.248 \| fine	1.365 \| good	1.629 \| good	14.367 \| good	0.252 \| good
2025-12-08T12:00:00.000Z	64 \| moderate	16.252 \| fine	72.615 \| fine	1.441 \| good	1.557 \| good	13.813 \| good	0.249 \| good
2025-12-08T13:00:00.000Z	66 \| moderate	16.82 \| fine	75.046 \| fine	1.648 \| good	1.692 \| good	13.567 \| good	0.256 \| good
2025-12-08T14:00:00.000Z	67 \| moderate	18.473 \| fine	82.352 \| fine	1.001 \| good	1.827 \| good	13.321 \| good	0.263 \| good
2025-12-08T15:00:00.000Z	66 \| moderate	16.995 \| fine	74.982 \| fine	2.234 \| good	1.962 \| good	13.075 \| good	0.271 \| good
2025-12-08T16:00:00.000Z	67 \| moderate	17.696 \| fine	78.982 \| fine	5.035 \| good	2.553 \| good	13.368 \| good	0.262 \| good
2025-12-08T17:00:00.000Z	67 \| moderate	17.952 \| fine	79.151 \| fine	7.066 \| good	3.143 \| good	13.661 \| good	0.254 \| good
2025-12-08T18:00:00.000Z	73 \| moderate	21.126 \| fine	92.968 \| fine	6.148 \| good	3.734 \| good	13.953 \| good	0.246 \| good
2025-12-08T19:00:00.000Z	77 \| moderate	23.409 \| fine	102.44 \| fine	6.515 \| good	3.51 \| good	12.485 \| good	0.221 \| good
2025-12-08T20:00:00.000Z	81 \| moderate	25.295 \| fine	109.686 \| fine	6.328 \| good	3.285 \| good	11.016 \| good	0.196 \| good
2025-12-08T21:00:00.000Z	84 \| moderate	27.27 \| fine	118.773 \| fine	4.759 \| good	3.061 \| good	9.548 \| good	0.171 \| good
2025-12-08T22:00:00.000Z	81 \| moderate	25.066 \| fine	109.644 \| fine	4.672 \| good	2.743 \| good	9.883 \| good	0.167 \| good
2025-12-08T23:00:00.000Z	71 \| moderate	20.377 \| fine	90.092 \| fine	4.116 \| good	2.425 \| good	10.218 \| good	0.163 \| good
2025-12-09T00:00:00.000Z	58 \| moderate	13.399 \| fine	60.066 \| fine	8.357 \| good	2.108 \| good	10.554 \| good	0.159 \| good
2025-12-09T01:00:00.000Z	54 \| moderate	11.174 \| good	49.482 \| good	10.165 \| good	1.918 \| good	12.189 \| good	0.185 \| good
2025-12-09T02:00:00.000Z	49 \| good	9.024 \| good	39.913 \| good	8.766 \| good	1.728 \| good	13.825 \| good	0.212 \| good
2025-12-09T03:00:00.000Z	49 \| good	8.546 \| good	38.016 \| good	6.146 \| good	1.539 \| good	15.46 \| good	0.238 \| good
2025-12-09T04:00:00.000Z	38 \| good	7.369 \| good	32.911 \| good	4.102 \| good	1.599 \| good	14.442 \| good	0.243 \| good
2025-12-09T05:00:00.000Z	38 \| good	6.852 \| good	30.13 \| good	3.574 \| good	1.659 \| good	13.424 \| good	0.248 \| good
2025-12-09T06:00:00.000Z	27 \| good	5.238 \| good	22.976 \| good	4.249 \| good	1.72 \| good	12.405 \| good	0.253 \| good
2025-12-09T07:00:00.000Z	22 \| good	4.037 \| good	17.182 \| good	4.174 \| good	1.64 \| good	11.895 \| good	0.253 \| good
2025-12-09T08:00:00.000Z	22 \| good	3.847 \| good	16.543 \| good	3.252 \| good	1.56 \| good	11.384 \| good	0.253 \| good
2025-12-09T09:00:00.000Z	44 \| good	7.531 \| good	33.636 \| good	2.435 \| good	1.481 \| good	10.873 \| good	0.253 \| good
2025-12-09T10:00:00.000Z	52 \| moderate	9.745 \| good	42.86 \| good	1.609 \| good	1.368 \| good	10.267 \| good	0.244 \| good
2025-12-09T11:00:00.000Z	52 \| moderate	10.405 \| good	45.91 \| good	1.063 \| good	1.255 \| good	9.662 \| good	0.235 \| good
2025-12-09T12:00:00.000Z	56 \| moderate	11.757 \| good	52.346 \| good	0.572 \| good	1.142 \| good	9.056 \| good	0.226 \| good
2025-12-09T13:00:00.000Z	56 \| moderate	11.931 \| good	52.915 \| good	0.353 \| good	1.227 \| good	9.377 \| good	0.226 \| good
2025-12-09T14:00:00.000Z	60 \| moderate	14.067 \| fine	63.179 \| fine	0.231 \| good	1.312 \| good	9.699 \| good	0.226 \| good

San Mateo

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San Mateo, California air quality map: Track AQI near you

0.30ppm

How accurate is California, USA air quality data?

Air quality data and pollutant measurements for California, USA adhere to strict US EPA standards. The data is collected from multiple reliable sources, including satellites and ground-based monitoring stations. This data is further analyzed and enhanced using machine learning and advanced algorithms that factor in elements such as traffic and population density, ensuring accurate and reliable results.

Source: Ambee Data Sources

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Frequently asked questions

How often is the air quality data for San Mateo, California updated?

The air quality for San Mateo, California is updated every hour.

When was the worst air quality at San Mateo, California in the last 24 hrs?

The worst air quality in San Mateo, California in the last 24 hours was observed at 10:00:00 on 2025-12-07.

When was the best air quality at San Mateo, California in the last 24 hrs?

In the last 24 hrs, the best air quality in San Mateo, California was observed at 11:00:00 on 2025-12-07.

What is the current air quality in San Mateo, California?

The current air quality in San Mateo, California is 58, categorized as Moderate based on real-time data.

What pollutant is the most common in San Mateo, California?

The most common pollutant in San Mateo, California is PM2.5.

What should I do if the air quality in San Mateo, California is poor?

If the air quality in San Mateo, California is poor, consider staying indoors and wearing a mask to protect yourself.

What is the current concentration of PM_2.5 in San Mateo, California?

The current PM_2.5 concentration at San Mateo, California is 12.552 μg/m³.

What is the current concentration of PM₁₀ in San Mateo, California?

The current PM₁₀ concentration at San Mateo, California is 48.986 μg/m³.

What is the current concentration of carbon monoxide (CO) in San Mateo, California?

The current carbon monoxide (CO) concentration at San Mateo, California is 0.45 ppm.

What is the current concentration of sulfur dioxide (SO₂) in San Mateo, California?

The current sulfur dioxide (SO₂) concentration at San Mateo, California is 0.445 ppb.

What is the current concentration of ozone (O₃) in San Mateo, California?

The current ozone (O₃) concentration at San Mateo, California is 8.509 ppm.

What is the current concentration of nitrogen dioxide (NO₂) in San Mateo, California?

The current nitrogen dioxide (NO₂) concentration at San Mateo, California is 10.965 ppb.

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Time	AQI	PM_2.5	PM₁₀	O₃	SO₂	NO₂	CO
2025-12-05T15:00:00.000Z	56 \| moderate	12.468 \| fine	50.135 \| good	6.351 \| good	0.455 \| good	19.703 \| good	0.615 \| good
2025-12-05T16:00:00.000Z	56 \| moderate	12.323 \| fine	45.957 \| good	5.487 \| good	0.438 \| good	15.389 \| good	0.81 \| good
2025-12-05T17:00:00.000Z	64 \| moderate	16.404 \| fine	71.346 \| fine	5.575 \| good	0.419 \| good	15.004 \| good	0.755 \| good
2025-12-05T18:00:00.000Z	62 \| moderate	15.393 \| fine	60.739 \| fine	10.778 \| good	0.464 \| good	11.911 \| good	0.607 \| good
2025-12-05T19:00:00.000Z	66 \| moderate	17.207 \| fine	71.549 \| fine	10.688 \| good	0.484 \| good	11.23 \| good	0.428 \| good
2025-12-05T20:00:00.000Z	69 \| moderate	19.026 \| fine	46.858 \| good	12.843 \| good	0.434 \| good	11.497 \| good	0.342 \| good
2025-12-05T21:00:00.000Z	67 \| moderate	18.162 \| fine	27.122 \| good	13.246 \| good	0.411 \| good	10.06 \| good	0.328 \| good
2025-12-05T22:00:00.000Z	66 \| moderate	16.771 \| fine	41.297 \| good	14.676 \| good	0.533 \| good	11 \| good	0.27 \| good
2025-12-05T23:00:00.000Z	73 \| moderate	20.881 \| fine	43.581 \| good	13.259 \| good	0.499 \| good	8.376 \| good	0.274 \| good
2025-12-06T00:00:00.000Z	64 \| moderate	16.213 \| fine	79.249 \| fine	12.999 \| good	0.485 \| good	11.164 \| good	0.256 \| good
2025-12-06T01:00:00.000Z	66 \| moderate	16.687 \| fine	74.624 \| fine	15.116 \| good	0.441 \| good	12.38 \| good	0.26 \| good
2025-12-06T02:00:00.000Z	67 \| moderate	18.219 \| fine	69.407 \| fine	12.789 \| good	0.369 \| good	14.866 \| good	0.306 \| good
2025-12-06T03:00:00.000Z	67 \| moderate	18.264 \| fine	76.721 \| fine	9.994 \| good	0.337 \| good	16.48 \| good	0.404 \| good
2025-12-06T04:00:00.000Z	69 \| moderate	19.494 \| fine	76.884 \| fine	10.957 \| good	0.35 \| good	16.035 \| good	0.479 \| good
2025-12-06T05:00:00.000Z	67 \| moderate	17.359 \| fine	88.212 \| fine	14.344 \| good	0.433 \| good	14.904 \| good	0.48 \| good
2025-12-06T06:00:00.000Z	66 \| moderate	16.583 \| fine	81.024 \| fine	12.833 \| good	0.399 \| good	11.799 \| good	0.541 \| good
2025-12-06T07:00:00.000Z	71 \| moderate	19.696 \| fine	75.612 \| fine	13.8 \| good	0.415 \| good	13.895 \| good	0.512 \| good
2025-12-06T08:00:00.000Z	71 \| moderate	19.891 \| fine	48.533 \| good	13.656 \| good	0.384 \| good	12.246 \| good	0.375 \| good
2025-12-06T09:00:00.000Z	71 \| moderate	20.121 \| fine	71.67 \| fine	14.093 \| good	0.404 \| good	12.3 \| good	0.376 \| good
2025-12-06T10:00:00.000Z	75 \| moderate	21.682 \| fine	97.576 \| fine	10.242 \| good	0.932 \| good	11.181 \| good	0.43 \| good
2025-12-06T11:00:00.000Z	56 \| moderate	12.38 \| fine	52.997 \| good	4.873 \| good	0.86 \| good	7.401 \| good	0.382 \| good
2025-12-06T12:00:00.000Z	68 \| moderate	14.592 \| fine	88.617 \| fine	5.027 \| good	0.316 \| good	8.184 \| good	0.371 \| good
2025-12-06T13:00:00.000Z	60 \| moderate	14.182 \| fine	60.734 \| fine	6.109 \| good	0.365 \| good	11.484 \| good	0.303 \| good
2025-12-06T14:00:00.000Z	58 \| moderate	13.436 \| fine	36.202 \| good	5.298 \| good	0.523 \| good	10.995 \| good	0.205 \| good
2025-12-06T15:00:00.000Z	64 \| moderate	15.661 \| fine	54.967 \| good	6.872 \| good	0.406 \| good	9.291 \| good	0.262 \| good
2025-12-06T16:00:00.000Z	64 \| moderate	15.652 \| fine	75.251 \| fine	3.9 \| good	0.373 \| good	7.952 \| good	0.294 \| good
2025-12-06T17:00:00.000Z	64 \| moderate	16.277 \| fine	72.902 \| fine	6.226 \| good	0.426 \| good	7.081 \| good	0.259 \| good
2025-12-06T18:00:00.000Z	64 \| moderate	16.33 \| fine	57.323 \| fine	8.067 \| good	0.516 \| good	6.653 \| good	0.297 \| good
2025-12-06T19:00:00.000Z	73 \| moderate	21.237 \| fine	96.446 \| fine	8.549 \| good	0.578 \| good	5.602 \| good	0.35 \| good
2025-12-06T20:00:00.000Z	73 \| moderate	21.275 \| fine	71.757 \| fine	8.831 \| good	0.558 \| good	6.521 \| good	0.332 \| good
2025-12-06T21:00:00.000Z	75 \| moderate	21.828 \| fine	51.58 \| good	9.852 \| good	0.572 \| good	7.384 \| good	0.351 \| good
2025-12-06T22:00:00.000Z	75 \| moderate	22.159 \| fine	93.756 \| fine	10.986 \| good	0.579 \| good	7.31 \| good	0.332 \| good
2025-12-06T23:00:00.000Z	71 \| moderate	19.539 \| fine	65.879 \| fine	10.278 \| good	0.493 \| good	6.905 \| good	0.298 \| good
2025-12-07T00:00:00.000Z	66 \| moderate	16.528 \| fine	73.694 \| fine	12.283 \| good	0.514 \| good	7.328 \| good	0.298 \| good
2025-12-07T01:00:00.000Z	64 \| moderate	15.7 \| fine	69.21 \| fine	13.064 \| good	0.444 \| good	9.51 \| good	0.319 \| good
2025-12-07T02:00:00.000Z	69 \| moderate	19.074 \| fine	58.927 \| fine	11.453 \| good	0.39 \| good	9.986 \| good	0.353 \| good
2025-12-07T03:00:00.000Z	60 \| moderate	14.079 \| fine	41.872 \| good	8.985 \| good	0.329 \| good	12.144 \| good	0.379 \| good
2025-12-07T04:00:00.000Z	56 \| moderate	11.955 \| good	32.778 \| good	13.396 \| good	0.318 \| good	12.044 \| good	0.502 \| good
2025-12-07T05:00:00.000Z	60 \| moderate	14.079 \| fine	24.015 \| good	9.842 \| good	0.278 \| good	10.168 \| good	0.545 \| good
2025-12-07T06:00:00.000Z	56 \| moderate	11.946 \| good	47.771 \| good	6.505 \| good	0.269 \| good	8.972 \| good	0.545 \| good
2025-12-07T07:00:00.000Z	67 \| moderate	18.365 \| fine	66.302 \| fine	8.163 \| good	0.269 \| good	9.184 \| good	0.53 \| good
2025-12-07T08:00:00.000Z	64 \| moderate	16.272 \| fine	68.538 \| fine	6.329 \| good	0.273 \| good	9.243 \| good	0.559 \| good
2025-12-07T09:00:00.000Z	66 \| moderate	17.094 \| fine	68.09 \| fine	8.761 \| good	0.324 \| good	8.122 \| good	0.49 \| good
2025-12-07T10:00:00.000Z	77 \| moderate	22.59 \| fine	93.139 \| fine	8.236 \| good	0.476 \| good	4.145 \| good	0.267 \| good
2025-12-07T11:00:00.000Z	56 \| moderate	12.11 \| fine	39.242 \| good	9.659 \| good	0.504 \| good	3.408 \| good	0.256 \| good
2025-12-07T12:00:00.000Z	64 \| moderate	16.192 \| fine	61.364 \| fine	5.154 \| good	0.338 \| good	7.356 \| good	0.22 \| good
2025-12-07T13:00:00.000Z	71 \| moderate	19.52 \| fine	84.237 \| fine	7.911 \| good	0.362 \| good	11.667 \| good	0.308 \| good
2025-12-07T14:00:00.000Z	58 \| moderate	12.552 \| fine	48.986 \| good	8.509 \| good	0.445 \| good	10.965 \| good	0.45 \| good
2025-12-07T14:00:00.000Z	58 \| moderate	12.552 \| fine	48.986 \| good	8.509 \| good	0.445 \| good	10.965 \| good	0.45 \| good
2025-12-07T15:00:00.000Z	62 \| moderate	14.897 \| fine	66.909 \| fine	4.145 \| good	1.428 \| good	16.762 \| good	0.243 \| good
2025-12-07T16:00:00.000Z	62 \| moderate	14.731 \| fine	66.183 \| fine	5.247 \| good	1.595 \| good	15.638 \| good	0.248 \| good
2025-12-07T17:00:00.000Z	66 \| moderate	16.616 \| fine	73.807 \| fine	4.495 \| good	1.762 \| good	14.515 \| good	0.254 \| good
2025-12-07T18:00:00.000Z	71 \| moderate	19.633 \| fine	86.32 \| fine	4.336 \| good	1.929 \| good	13.392 \| good	0.259 \| good
2025-12-07T19:00:00.000Z	71 \| moderate	20.407 \| fine	90.225 \| fine	5.836 \| good	2.083 \| good	12.451 \| good	0.237 \| good
2025-12-07T20:00:00.000Z	71 \| moderate	20.141 \| fine	88.984 \| fine	6.196 \| good	2.236 \| good	11.51 \| good	0.215 \| good
2025-12-07T21:00:00.000Z	67 \| moderate	18.335 \| fine	80.753 \| fine	6.598 \| good	2.39 \| good	10.569 \| good	0.193 \| good
2025-12-07T22:00:00.000Z	62 \| moderate	15.196 \| fine	67.499 \| fine	8.52 \| good	2.24 \| good	11.478 \| good	0.186 \| good
2025-12-07T23:00:00.000Z	58 \| moderate	13.272 \| fine	59.287 \| fine	10.168 \| good	2.09 \| good	12.387 \| good	0.18 \| good
2025-12-08T00:00:00.000Z	54 \| moderate	11.151 \| good	49.734 \| good	11.23 \| good	1.94 \| good	13.296 \| good	0.174 \| good
2025-12-08T01:00:00.000Z	44 \| good	8.152 \| good	36.017 \| good	9.674 \| good	1.846 \| good	14.261 \| good	0.197 \| good
2025-12-08T02:00:00.000Z	38 \| good	7.442 \| good	32.914 \| good	7.5 \| good	1.753 \| good	15.226 \| good	0.221 \| good
2025-12-08T03:00:00.000Z	44 \| good	7.872 \| good	34.6 \| good	6.453 \| good	1.659 \| good	16.192 \| good	0.244 \| good
2025-12-08T04:00:00.000Z	33 \| good	6.445 \| good	28.384 \| good	5.649 \| good	1.771 \| good	16.052 \| good	0.25 \| good
2025-12-08T05:00:00.000Z	27 \| good	5.391 \| good	23.645 \| good	5.249 \| good	1.882 \| good	15.911 \| good	0.256 \| good
2025-12-08T06:00:00.000Z	16 \| good	3.498 \| good	14.979 \| good	3.475 \| good	1.994 \| good	15.771 \| good	0.262 \| good
2025-12-08T07:00:00.000Z	27 \| good	4.897 \| good	21.536 \| good	1.441 \| good	1.92 \| good	15.672 \| good	0.261 \| good
2025-12-08T08:00:00.000Z	49 \| good	8.526 \| good	37.804 \| good	2.284 \| good	1.846 \| good	15.573 \| good	0.26 \| good
2025-12-08T09:00:00.000Z	58 \| moderate	12.567 \| fine	55.956 \| fine	1.85 \| good	1.772 \| good	15.474 \| good	0.259 \| good
2025-12-08T10:00:00.000Z	58 \| moderate	12.96 \| fine	58.351 \| fine	1.537 \| good	1.7 \| good	14.92 \| good	0.256 \| good
2025-12-08T11:00:00.000Z	60 \| moderate	14.399 \| fine	64.248 \| fine	1.365 \| good	1.629 \| good	14.367 \| good	0.252 \| good
2025-12-08T12:00:00.000Z	64 \| moderate	16.252 \| fine	72.615 \| fine	1.441 \| good	1.557 \| good	13.813 \| good	0.249 \| good
2025-12-08T13:00:00.000Z	66 \| moderate	16.82 \| fine	75.046 \| fine	1.648 \| good	1.692 \| good	13.567 \| good	0.256 \| good
2025-12-08T14:00:00.000Z	67 \| moderate	18.473 \| fine	82.352 \| fine	1.001 \| good	1.827 \| good	13.321 \| good	0.263 \| good
2025-12-08T15:00:00.000Z	66 \| moderate	16.995 \| fine	74.982 \| fine	2.234 \| good	1.962 \| good	13.075 \| good	0.271 \| good
2025-12-08T16:00:00.000Z	67 \| moderate	17.696 \| fine	78.982 \| fine	5.035 \| good	2.553 \| good	13.368 \| good	0.262 \| good
2025-12-08T17:00:00.000Z	67 \| moderate	17.952 \| fine	79.151 \| fine	7.066 \| good	3.143 \| good	13.661 \| good	0.254 \| good
2025-12-08T18:00:00.000Z	73 \| moderate	21.126 \| fine	92.968 \| fine	6.148 \| good	3.734 \| good	13.953 \| good	0.246 \| good
2025-12-08T19:00:00.000Z	77 \| moderate	23.409 \| fine	102.44 \| fine	6.515 \| good	3.51 \| good	12.485 \| good	0.221 \| good
2025-12-08T20:00:00.000Z	81 \| moderate	25.295 \| fine	109.686 \| fine	6.328 \| good	3.285 \| good	11.016 \| good	0.196 \| good
2025-12-08T21:00:00.000Z	84 \| moderate	27.27 \| fine	118.773 \| fine	4.759 \| good	3.061 \| good	9.548 \| good	0.171 \| good
2025-12-08T22:00:00.000Z	81 \| moderate	25.066 \| fine	109.644 \| fine	4.672 \| good	2.743 \| good	9.883 \| good	0.167 \| good
2025-12-08T23:00:00.000Z	71 \| moderate	20.377 \| fine	90.092 \| fine	4.116 \| good	2.425 \| good	10.218 \| good	0.163 \| good
2025-12-09T00:00:00.000Z	58 \| moderate	13.399 \| fine	60.066 \| fine	8.357 \| good	2.108 \| good	10.554 \| good	0.159 \| good
2025-12-09T01:00:00.000Z	54 \| moderate	11.174 \| good	49.482 \| good	10.165 \| good	1.918 \| good	12.189 \| good	0.185 \| good
2025-12-09T02:00:00.000Z	49 \| good	9.024 \| good	39.913 \| good	8.766 \| good	1.728 \| good	13.825 \| good	0.212 \| good
2025-12-09T03:00:00.000Z	49 \| good	8.546 \| good	38.016 \| good	6.146 \| good	1.539 \| good	15.46 \| good	0.238 \| good
2025-12-09T04:00:00.000Z	38 \| good	7.369 \| good	32.911 \| good	4.102 \| good	1.599 \| good	14.442 \| good	0.243 \| good
2025-12-09T05:00:00.000Z	38 \| good	6.852 \| good	30.13 \| good	3.574 \| good	1.659 \| good	13.424 \| good	0.248 \| good
2025-12-09T06:00:00.000Z	27 \| good	5.238 \| good	22.976 \| good	4.249 \| good	1.72 \| good	12.405 \| good	0.253 \| good
2025-12-09T07:00:00.000Z	22 \| good	4.037 \| good	17.182 \| good	4.174 \| good	1.64 \| good	11.895 \| good	0.253 \| good
2025-12-09T08:00:00.000Z	22 \| good	3.847 \| good	16.543 \| good	3.252 \| good	1.56 \| good	11.384 \| good	0.253 \| good
2025-12-09T09:00:00.000Z	44 \| good	7.531 \| good	33.636 \| good	2.435 \| good	1.481 \| good	10.873 \| good	0.253 \| good
2025-12-09T10:00:00.000Z	52 \| moderate	9.745 \| good	42.86 \| good	1.609 \| good	1.368 \| good	10.267 \| good	0.244 \| good
2025-12-09T11:00:00.000Z	52 \| moderate	10.405 \| good	45.91 \| good	1.063 \| good	1.255 \| good	9.662 \| good	0.235 \| good
2025-12-09T12:00:00.000Z	56 \| moderate	11.757 \| good	52.346 \| good	0.572 \| good	1.142 \| good	9.056 \| good	0.226 \| good
2025-12-09T13:00:00.000Z	56 \| moderate	11.931 \| good	52.915 \| good	0.353 \| good	1.227 \| good	9.377 \| good	0.226 \| good
2025-12-09T14:00:00.000Z	60 \| moderate	14.067 \| fine	63.179 \| fine	0.231 \| good	1.312 \| good	9.699 \| good	0.226 \| good

San Mateo, California live air quality index now

Major air pollutants in San Mateo, California

Particulate Matter2.5 (PM2.5)

Particulate Matter10 (PM10)

Ozone (O3)

Sulfur Dioxide (SO2)

Nitrogen Dioxide (NO2)

Carbon Monoxide (CO)

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San Mateo, California air quality map: Track AQI near you

Air quality in nearby cities

Burlingame, California

Foster City, California

Hillsborough, California

Belmont, California

Millbrae, California

San Carlos, California

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Frequently asked questions

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What is the current concentration of PM2.5 in San Mateo, California?

What is the current concentration of PM10 in San Mateo, California?

What is the current concentration of carbon monoxide (CO) in San Mateo, California?

What is the current concentration of sulfur dioxide (SO2) in San Mateo, California?

What is the current concentration of ozone (O3) in San Mateo, California?

What is the current concentration of nitrogen dioxide (NO2) in San Mateo, California?

Particulate Matter_2.5 (PM_2.5)

Particulate Matter₁₀ (PM₁₀)

Ozone (O₃)

Sulfur Dioxide (SO₂)

Nitrogen Dioxide (NO₂)

What is the current concentration of PM_2.5 in San Mateo, California?

What is the current concentration of PM₁₀ in San Mateo, California?

What is the current concentration of sulfur dioxide (SO₂) in San Mateo, California?

What is the current concentration of ozone (O₃) in San Mateo, California?

What is the current concentration of nitrogen dioxide (NO₂) in San Mateo, California?