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

The current PM10 concentration at San Mateo, California is 11.578 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 0.938 ppb.

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

The current ozone (O3) concentration at San Mateo, California is 46.912 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 7.354 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 1.896 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)

Good

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)

1.90 μg/m³

12.1

35.5

55.5

250.5

500.5+

Particulate Matter₁₀ (PM₁₀)

11.58 μg/m³

155

255

425

605+

Ozone (O₃)

46.91 ppb

201

201+

Sulfur Dioxide (SO₂)

0.94 ppb

186

605

1005+

Nitrogen Dioxide (NO₂)

7.35 ppb

101

361

1250

2050+

Carbon Monoxide (CO)

0.34 ppm

4.5

9.5

12.5

230.5

50.5+

Pollen Level

Very high

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
2026-04-17T03:00:00.000Z	33 \| good	2.733 \| good	11.099 \| good	35.596 \| good	0.505 \| good	6.647 \| good	0.172 \| good
2026-04-17T04:00:00.000Z	36 \| good	2.891 \| good	7.874 \| good	39.254 \| good	0.352 \| good	6.102 \| good	0.266 \| good
2026-04-17T05:00:00.000Z	35 \| good	6.291 \| good	29.928 \| good	37.981 \| good	0.353 \| good	6.201 \| good	0.3 \| good
2026-04-17T06:00:00.000Z	29 \| good	5.384 \| good	21.814 \| good	31.035 \| good	0.401 \| good	5.932 \| good	0.3 \| good
2026-04-17T07:00:00.000Z	38 \| good	6.917 \| good	34.296 \| good	35.78 \| good	0.437 \| good	6.996 \| good	0.282 \| good
2026-04-17T08:00:00.000Z	30 \| good	3.717 \| good	20.45 \| good	32.495 \| good	0.373 \| good	7.301 \| good	0.262 \| good
2026-04-17T09:00:00.000Z	31 \| good	3.561 \| good	14.039 \| good	34.198 \| good	0.352 \| good	7.366 \| good	0.262 \| good
2026-04-17T10:00:00.000Z	33 \| good	3.155 \| good	15.101 \| good	36.211 \| good	0.385 \| good	6.075 \| good	0.246 \| good
2026-04-17T11:00:00.000Z	31 \| good	4.177 \| good	20.956 \| good	33.6 \| good	0.386 \| good	5.74 \| good	0.246 \| good
2026-04-17T12:00:00.000Z	39 \| good	1.179 \| good	4.916 \| good	42.19 \| good	0.386 \| good	5.464 \| good	0.246 \| good
2026-04-17T13:00:00.000Z	36 \| good	2.285 \| good	9.361 \| good	38.628 \| good	0.419 \| good	7.339 \| good	0.295 \| good
2026-04-17T14:00:00.000Z	27 \| good	2.031 \| good	13.514 \| good	29.26 \| good	0.404 \| good	13.443 \| good	0.361 \| good
2026-04-17T15:00:00.000Z	28 \| good	4.027 \| good	19.959 \| good	29.533 \| good	0.434 \| good	16.954 \| good	0.436 \| good
2026-04-17T16:00:00.000Z	34 \| good	3.925 \| good	21.802 \| good	37.074 \| good	0.529 \| good	14.221 \| good	0.395 \| good
2026-04-17T17:00:00.000Z	34 \| good	3.822 \| good	16.12 \| good	37.208 \| good	0.777 \| good	7.705 \| good	0.284 \| good
2026-04-17T18:00:00.000Z	33 \| good	2.876 \| good	8.747 \| good	36.013 \| good	0.752 \| good	5.03 \| good	0.237 \| good
2026-04-17T19:00:00.000Z	34 \| good	3.769 \| good	31.403 \| good	36.612 \| good	0.569 \| good	4.145 \| good	0.218 \| good
2026-04-17T20:00:00.000Z	34 \| good	2.684 \| good	14.071 \| good	37.252 \| good	0.453 \| good	3.983 \| good	0.235 \| good
2026-04-17T21:00:00.000Z	39 \| good	3.609 \| good	18.649 \| good	41.652 \| good	0.552 \| good	4.2 \| good	0.255 \| good
2026-04-17T22:00:00.000Z	31 \| good	3.154 \| good	14.964 \| good	33.096 \| good	0.612 \| good	4.479 \| good	0.238 \| good
2026-04-17T23:00:00.000Z	27 \| good	0.692 \| good	2.586 \| good	29.321 \| good	0.924 \| good	4.229 \| good	0.238 \| good
2026-04-18T00:00:00.000Z	28 \| good	0.44 \| good	2.918 \| good	29.85 \| good	0.689 \| good	6.155 \| good	0.268 \| good
2026-04-18T01:00:00.000Z	31 \| good	3.268 \| good	16.024 \| good	34.364 \| good	1.89 \| good	5.585 \| good	0.248 \| good
2026-04-18T02:00:00.000Z	44 \| good	1.52 \| good	5.283 \| good	46.656 \| good	0.935 \| good	8.564 \| good	0.286 \| good
2026-04-18T03:00:00.000Z	47 \| good	2.828 \| good	17.024 \| good	51.387 \| good	0.565 \| good	15.396 \| good	0.303 \| good
2026-04-18T04:00:00.000Z	35 \| good	5.448 \| good	28.208 \| good	38.111 \| good	0.531 \| good	5.034 \| good	0.318 \| good
2026-04-18T05:00:00.000Z	30 \| good	3.878 \| good	19.884 \| good	32.278 \| good	0.462 \| good	4.116 \| good	0.3 \| good
2026-04-18T06:00:00.000Z	31 \| good	4.059 \| good	26.123 \| good	33.194 \| good	0.443 \| good	3.067 \| good	0.316 \| good
2026-04-18T07:00:00.000Z	31 \| good	3.789 \| good	13.282 \| good	32.799 \| good	0.424 \| good	5.917 \| good	0.335 \| good
2026-04-18T08:00:00.000Z	30 \| good	3.913 \| good	16.862 \| good	32.217 \| good	0.456 \| good	5.425 \| good	0.335 \| good
2026-04-18T09:00:00.000Z	30 \| good	2.588 \| good	13.763 \| good	31.58 \| good	0.457 \| good	5.993 \| good	0.335 \| good
2026-04-18T10:00:00.000Z	27 \| good	2.444 \| good	14 \| good	29.112 \| good	0.539 \| good	7.197 \| good	0.203 \| good
2026-04-18T11:00:00.000Z	27 \| good	2.591 \| good	15.98 \| good	28.712 \| good	0.523 \| good	6.712 \| good	0.175 \| good
2026-04-18T12:00:00.000Z	33 \| good	4.113 \| good	31.024 \| good	35.854 \| good	0.239 \| good	5.356 \| good	0.411 \| good
2026-04-18T13:00:00.000Z	21 \| good	3.279 \| good	14.828 \| good	23 \| good	0.66 \| good	4.217 \| good	0.362 \| good
2026-04-18T14:00:00.000Z	28 \| good	4.039 \| good	15.114 \| good	29.675 \| good	0.481 \| good	7.404 \| good	0.345 \| good
2026-04-18T15:00:00.000Z	20 \| good	3.446 \| good	18.344 \| good	21.738 \| good	0.464 \| good	14.318 \| good	0.461 \| good
2026-04-18T16:00:00.000Z	19 \| good	3.481 \| good	18.194 \| good	20.854 \| good	0.563 \| good	9.287 \| good	0.396 \| good
2026-04-18T17:00:00.000Z	38 \| good	6.944 \| good	26.542 \| good	22.089 \| good	0.645 \| good	12.001 \| good	0.415 \| good
2026-04-18T18:00:00.000Z	49 \| good	8.79 \| good	31.808 \| good	27.452 \| good	0.692 \| good	8.267 \| good	0.382 \| good
2026-04-18T19:00:00.000Z	38 \| good	7.198 \| good	34.341 \| good	28.836 \| good	0.747 \| good	8.624 \| good	0.353 \| good
2026-04-18T20:00:00.000Z	33 \| good	6.399 \| good	36.485 \| good	32.787 \| good	0.786 \| good	7.059 \| good	0.318 \| good
2026-04-18T21:00:00.000Z	32 \| good	4.798 \| good	19.374 \| good	35.446 \| good	0.792 \| good	7.889 \| good	0.335 \| good
2026-04-18T22:00:00.000Z	38 \| good	4.294 \| good	23.47 \| good	41.467 \| good	1.045 \| good	6.168 \| good	0.318 \| good
2026-04-18T23:00:00.000Z	39 \| good	4.838 \| good	21.044 \| good	41.769 \| good	0.639 \| good	6.918 \| good	0.318 \| good
2026-04-19T00:00:00.000Z	44 \| good	2.977 \| good	10.133 \| good	46.887 \| good	0.602 \| good	6.845 \| good	0.318 \| good
2026-04-19T01:00:00.000Z	44 \| good	1.896 \| good	11.578 \| good	46.912 \| good	0.938 \| good	7.354 \| good	0.337 \| good
2026-04-19T02:00:00.000Z	44 \| good	1.896 \| good	11.578 \| good	46.912 \| good	0.938 \| good	7.354 \| good	0.337 \| good
2026-04-19T03:00:00.000Z	34 \| good	3.498 \| good	15.196 \| good	36.737 \| good	1.442 \| good	15.124 \| good	0.197 \| good
2026-04-19T04:00:00.000Z	34 \| good	2.865 \| good	12.059 \| good	36.735 \| good	1.417 \| good	14.867 \| good	0.208 \| good
2026-04-19T05:00:00.000Z	33 \| good	2.01 \| good	8.156 \| good	35.716 \| good	1.391 \| good	14.611 \| good	0.219 \| good
2026-04-19T06:00:00.000Z	33 \| good	1.867 \| good	7.707 \| good	36.208 \| good	1.366 \| good	14.354 \| good	0.23 \| good
2026-04-19T07:00:00.000Z	35 \| good	1.306 \| good	5.452 \| good	37.775 \| good	1.24 \| good	13.48 \| good	0.223 \| good
2026-04-19T08:00:00.000Z	35 \| good	1.364 \| good	5.371 \| good	37.934 \| good	1.113 \| good	12.606 \| good	0.216 \| good
2026-04-19T09:00:00.000Z	34 \| good	1.164 \| good	4.959 \| good	37.351 \| good	0.987 \| good	11.732 \| good	0.21 \| good
2026-04-19T10:00:00.000Z	32 \| good	1.546 \| good	6.112 \| good	35.197 \| good	0.967 \| good	11.365 \| good	0.204 \| good
2026-04-19T11:00:00.000Z	31 \| good	1.81 \| good	7.647 \| good	33.281 \| good	0.946 \| good	10.998 \| good	0.199 \| good
2026-04-19T12:00:00.000Z	34 \| good	0.769 \| good	2.936 \| good	37.118 \| good	0.926 \| good	10.631 \| good	0.193 \| good
2026-04-19T13:00:00.000Z	25 \| good	3.232 \| good	13.731 \| good	27.027 \| good	0.981 \| good	9.93 \| good	0.19 \| good
2026-04-19T14:00:00.000Z	23 \| good	3.697 \| good	16.171 \| good	25.191 \| good	1.035 \| good	9.229 \| good	0.186 \| good
2026-04-19T15:00:00.000Z	28 \| good	4.249 \| good	18.154 \| good	30.166 \| good	1.089 \| good	8.528 \| good	0.183 \| good
2026-04-19T16:00:00.000Z	29 \| good	4.194 \| good	18.152 \| good	31.469 \| good	1.181 \| good	6.8 \| good	0.168 \| good
2026-04-19T17:00:00.000Z	30 \| good	4.582 \| good	19.901 \| good	32.036 \| good	1.273 \| good	5.072 \| good	0.152 \| good
2026-04-19T18:00:00.000Z	29 \| good	4.407 \| good	19.472 \| good	31.204 \| good	1.366 \| good	3.344 \| good	0.137 \| good
2026-04-19T19:00:00.000Z	31 \| good	4.934 \| good	21.274 \| good	33.715 \| good	1.288 \| good	2.896 \| good	0.134 \| good
2026-04-19T20:00:00.000Z	31 \| good	4.123 \| good	18.094 \| good	34.114 \| good	1.21 \| good	2.449 \| good	0.131 \| good
2026-04-19T21:00:00.000Z	31 \| good	3.713 \| good	16.486 \| good	33.825 \| good	1.133 \| good	2.001 \| good	0.128 \| good
2026-04-19T22:00:00.000Z	30 \| good	2.827 \| good	11.677 \| good	31.812 \| good	1.057 \| good	2.027 \| good	0.129 \| good
2026-04-19T23:00:00.000Z	30 \| good	2.25 \| good	8.884 \| good	32.205 \| good	0.981 \| good	2.053 \| good	0.129 \| good
2026-04-20T00:00:00.000Z	31 \| good	2.416 \| good	9.675 \| good	33.34 \| good	0.905 \| good	2.079 \| good	0.13 \| good
2026-04-20T01:00:00.000Z	31 \| good	1.92 \| good	8.191 \| good	33.766 \| good	0.882 \| good	2.805 \| good	0.134 \| good
2026-04-20T02:00:00.000Z	31 \| good	2.366 \| good	9.443 \| good	34.099 \| good	0.858 \| good	3.531 \| good	0.138 \| good
2026-04-20T03:00:00.000Z	29 \| good	2.269 \| good	9.277 \| good	30.961 \| good	0.835 \| good	4.257 \| good	0.143 \| good
2026-04-20T04:00:00.000Z	25 \| good	2.504 \| good	10.416 \| good	27.067 \| good	0.861 \| good	4.94 \| good	0.146 \| good
2026-04-20T05:00:00.000Z	26 \| good	1.996 \| good	8.277 \| good	27.678 \| good	0.888 \| good	5.623 \| good	0.149 \| good
2026-04-20T06:00:00.000Z	28 \| good	2.591 \| good	10.89 \| good	30.243 \| good	0.914 \| good	6.305 \| good	0.153 \| good
2026-04-20T07:00:00.000Z	30 \| good	2.741 \| good	11.737 \| good	31.632 \| good	0.875 \| good	6.742 \| good	0.156 \| good
2026-04-20T08:00:00.000Z	29 \| good	3.437 \| good	14.285 \| good	31.329 \| good	0.836 \| good	7.178 \| good	0.16 \| good
2026-04-20T09:00:00.000Z	27 \| good	3.531 \| good	15.317 \| good	29.383 \| good	0.796 \| good	7.614 \| good	0.163 \| good
2026-04-20T10:00:00.000Z	28 \| good	3.645 \| good	16.055 \| good	30.41 \| good	0.756 \| good	6.493 \| good	0.157 \| good
2026-04-20T11:00:00.000Z	29 \| good	3.837 \| good	17.028 \| good	30.697 \| good	0.716 \| good	5.372 \| good	0.151 \| good
2026-04-20T12:00:00.000Z	26 \| good	2.756 \| good	11.008 \| good	28.419 \| good	0.676 \| good	4.251 \| good	0.144 \| good
2026-04-20T13:00:00.000Z	22 \| good	2.459 \| good	10.181 \| good	23.743 \| good	0.677 \| good	4.221 \| good	0.144 \| good
2026-04-20T14:00:00.000Z	22 \| good	3.643 \| good	16.028 \| good	19.788 \| good	0.679 \| good	4.191 \| good	0.144 \| good
2026-04-20T15:00:00.000Z	27 \| good	4.854 \| good	21.305 \| good	22.878 \| good	0.68 \| good	4.161 \| good	0.144 \| good
2026-04-20T16:00:00.000Z	33 \| good	5.518 \| good	23.789 \| good	25.928 \| good	0.692 \| good	4.18 \| good	0.143 \| good
2026-04-20T17:00:00.000Z	27 \| good	4.909 \| good	21.522 \| good	28.363 \| good	0.705 \| good	4.198 \| good	0.143 \| good
2026-04-20T18:00:00.000Z	27 \| good	3.928 \| good	17.349 \| good	28.909 \| good	0.717 \| good	4.217 \| good	0.142 \| good
2026-04-20T19:00:00.000Z	30 \| good	2.506 \| good	10.531 \| good	32.224 \| good	0.621 \| good	3.481 \| good	0.137 \| good
2026-04-20T20:00:00.000Z	33 \| good	2.078 \| good	8.367 \| good	35.691 \| good	0.524 \| good	2.746 \| good	0.131 \| good
2026-04-20T21:00:00.000Z	33 \| good	1.533 \| good	6.192 \| good	36.498 \| good	0.428 \| good	2.01 \| good	0.126 \| good
2026-04-20T22:00:00.000Z	31 \| good	1.824 \| good	7.816 \| good	33.031 \| good	0.435 \| good	2.129 \| good	0.125 \| good
2026-04-20T23:00:00.000Z	29 \| good	2.526 \| good	10.33 \| good	31.304 \| good	0.442 \| good	2.248 \| good	0.125 \| good
2026-04-21T00:00:00.000Z	38 \| good	6.931 \| good	10.625 \| good	40.723 \| good	0.451 \| good	2.377 \| good	0.125 \| good
2026-04-21T01:00:00.000Z	29 \| good	3.449 \| good	15.3 \| good	30.99 \| good	0.52 \| good	3.166 \| good	0.128 \| good
2026-04-21T02:00:00.000Z	30 \| good	2.899 \| good	12.341 \| good	31.752 \| good	0.591 \| good	3.966 \| good	0.131 \| good

San Mateo

Get reliable air quality data to drive your business

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

0.31ppm

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 06:00:00 on 2026-04-18.

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 04:00:00 on 2026-04-18.

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

The current air quality in San Mateo, California is 44, categorized as Good based on real-time data.

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

The most common pollutant in San Mateo, California is O3.

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 1.896 μg/m³.

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

The current PM₁₀ concentration at San Mateo, California is 11.578 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 0.337 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 0.938 ppb.

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

The current ozone (O₃) concentration at San Mateo, California is 46.912 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 7.354 ppb.

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Time	AQI	PM_2.5	PM₁₀	O₃	SO₂	NO₂	CO
2026-04-17T03:00:00.000Z	33 \| good	2.733 \| good	11.099 \| good	35.596 \| good	0.505 \| good	6.647 \| good	0.172 \| good
2026-04-17T04:00:00.000Z	36 \| good	2.891 \| good	7.874 \| good	39.254 \| good	0.352 \| good	6.102 \| good	0.266 \| good
2026-04-17T05:00:00.000Z	35 \| good	6.291 \| good	29.928 \| good	37.981 \| good	0.353 \| good	6.201 \| good	0.3 \| good
2026-04-17T06:00:00.000Z	29 \| good	5.384 \| good	21.814 \| good	31.035 \| good	0.401 \| good	5.932 \| good	0.3 \| good
2026-04-17T07:00:00.000Z	38 \| good	6.917 \| good	34.296 \| good	35.78 \| good	0.437 \| good	6.996 \| good	0.282 \| good
2026-04-17T08:00:00.000Z	30 \| good	3.717 \| good	20.45 \| good	32.495 \| good	0.373 \| good	7.301 \| good	0.262 \| good
2026-04-17T09:00:00.000Z	31 \| good	3.561 \| good	14.039 \| good	34.198 \| good	0.352 \| good	7.366 \| good	0.262 \| good
2026-04-17T10:00:00.000Z	33 \| good	3.155 \| good	15.101 \| good	36.211 \| good	0.385 \| good	6.075 \| good	0.246 \| good
2026-04-17T11:00:00.000Z	31 \| good	4.177 \| good	20.956 \| good	33.6 \| good	0.386 \| good	5.74 \| good	0.246 \| good
2026-04-17T12:00:00.000Z	39 \| good	1.179 \| good	4.916 \| good	42.19 \| good	0.386 \| good	5.464 \| good	0.246 \| good
2026-04-17T13:00:00.000Z	36 \| good	2.285 \| good	9.361 \| good	38.628 \| good	0.419 \| good	7.339 \| good	0.295 \| good
2026-04-17T14:00:00.000Z	27 \| good	2.031 \| good	13.514 \| good	29.26 \| good	0.404 \| good	13.443 \| good	0.361 \| good
2026-04-17T15:00:00.000Z	28 \| good	4.027 \| good	19.959 \| good	29.533 \| good	0.434 \| good	16.954 \| good	0.436 \| good
2026-04-17T16:00:00.000Z	34 \| good	3.925 \| good	21.802 \| good	37.074 \| good	0.529 \| good	14.221 \| good	0.395 \| good
2026-04-17T17:00:00.000Z	34 \| good	3.822 \| good	16.12 \| good	37.208 \| good	0.777 \| good	7.705 \| good	0.284 \| good
2026-04-17T18:00:00.000Z	33 \| good	2.876 \| good	8.747 \| good	36.013 \| good	0.752 \| good	5.03 \| good	0.237 \| good
2026-04-17T19:00:00.000Z	34 \| good	3.769 \| good	31.403 \| good	36.612 \| good	0.569 \| good	4.145 \| good	0.218 \| good
2026-04-17T20:00:00.000Z	34 \| good	2.684 \| good	14.071 \| good	37.252 \| good	0.453 \| good	3.983 \| good	0.235 \| good
2026-04-17T21:00:00.000Z	39 \| good	3.609 \| good	18.649 \| good	41.652 \| good	0.552 \| good	4.2 \| good	0.255 \| good
2026-04-17T22:00:00.000Z	31 \| good	3.154 \| good	14.964 \| good	33.096 \| good	0.612 \| good	4.479 \| good	0.238 \| good
2026-04-17T23:00:00.000Z	27 \| good	0.692 \| good	2.586 \| good	29.321 \| good	0.924 \| good	4.229 \| good	0.238 \| good
2026-04-18T00:00:00.000Z	28 \| good	0.44 \| good	2.918 \| good	29.85 \| good	0.689 \| good	6.155 \| good	0.268 \| good
2026-04-18T01:00:00.000Z	31 \| good	3.268 \| good	16.024 \| good	34.364 \| good	1.89 \| good	5.585 \| good	0.248 \| good
2026-04-18T02:00:00.000Z	44 \| good	1.52 \| good	5.283 \| good	46.656 \| good	0.935 \| good	8.564 \| good	0.286 \| good
2026-04-18T03:00:00.000Z	47 \| good	2.828 \| good	17.024 \| good	51.387 \| good	0.565 \| good	15.396 \| good	0.303 \| good
2026-04-18T04:00:00.000Z	35 \| good	5.448 \| good	28.208 \| good	38.111 \| good	0.531 \| good	5.034 \| good	0.318 \| good
2026-04-18T05:00:00.000Z	30 \| good	3.878 \| good	19.884 \| good	32.278 \| good	0.462 \| good	4.116 \| good	0.3 \| good
2026-04-18T06:00:00.000Z	31 \| good	4.059 \| good	26.123 \| good	33.194 \| good	0.443 \| good	3.067 \| good	0.316 \| good
2026-04-18T07:00:00.000Z	31 \| good	3.789 \| good	13.282 \| good	32.799 \| good	0.424 \| good	5.917 \| good	0.335 \| good
2026-04-18T08:00:00.000Z	30 \| good	3.913 \| good	16.862 \| good	32.217 \| good	0.456 \| good	5.425 \| good	0.335 \| good
2026-04-18T09:00:00.000Z	30 \| good	2.588 \| good	13.763 \| good	31.58 \| good	0.457 \| good	5.993 \| good	0.335 \| good
2026-04-18T10:00:00.000Z	27 \| good	2.444 \| good	14 \| good	29.112 \| good	0.539 \| good	7.197 \| good	0.203 \| good
2026-04-18T11:00:00.000Z	27 \| good	2.591 \| good	15.98 \| good	28.712 \| good	0.523 \| good	6.712 \| good	0.175 \| good
2026-04-18T12:00:00.000Z	33 \| good	4.113 \| good	31.024 \| good	35.854 \| good	0.239 \| good	5.356 \| good	0.411 \| good
2026-04-18T13:00:00.000Z	21 \| good	3.279 \| good	14.828 \| good	23 \| good	0.66 \| good	4.217 \| good	0.362 \| good
2026-04-18T14:00:00.000Z	28 \| good	4.039 \| good	15.114 \| good	29.675 \| good	0.481 \| good	7.404 \| good	0.345 \| good
2026-04-18T15:00:00.000Z	20 \| good	3.446 \| good	18.344 \| good	21.738 \| good	0.464 \| good	14.318 \| good	0.461 \| good
2026-04-18T16:00:00.000Z	19 \| good	3.481 \| good	18.194 \| good	20.854 \| good	0.563 \| good	9.287 \| good	0.396 \| good
2026-04-18T17:00:00.000Z	38 \| good	6.944 \| good	26.542 \| good	22.089 \| good	0.645 \| good	12.001 \| good	0.415 \| good
2026-04-18T18:00:00.000Z	49 \| good	8.79 \| good	31.808 \| good	27.452 \| good	0.692 \| good	8.267 \| good	0.382 \| good
2026-04-18T19:00:00.000Z	38 \| good	7.198 \| good	34.341 \| good	28.836 \| good	0.747 \| good	8.624 \| good	0.353 \| good
2026-04-18T20:00:00.000Z	33 \| good	6.399 \| good	36.485 \| good	32.787 \| good	0.786 \| good	7.059 \| good	0.318 \| good
2026-04-18T21:00:00.000Z	32 \| good	4.798 \| good	19.374 \| good	35.446 \| good	0.792 \| good	7.889 \| good	0.335 \| good
2026-04-18T22:00:00.000Z	38 \| good	4.294 \| good	23.47 \| good	41.467 \| good	1.045 \| good	6.168 \| good	0.318 \| good
2026-04-18T23:00:00.000Z	39 \| good	4.838 \| good	21.044 \| good	41.769 \| good	0.639 \| good	6.918 \| good	0.318 \| good
2026-04-19T00:00:00.000Z	44 \| good	2.977 \| good	10.133 \| good	46.887 \| good	0.602 \| good	6.845 \| good	0.318 \| good
2026-04-19T01:00:00.000Z	44 \| good	1.896 \| good	11.578 \| good	46.912 \| good	0.938 \| good	7.354 \| good	0.337 \| good
2026-04-19T02:00:00.000Z	44 \| good	1.896 \| good	11.578 \| good	46.912 \| good	0.938 \| good	7.354 \| good	0.337 \| good
2026-04-19T03:00:00.000Z	34 \| good	3.498 \| good	15.196 \| good	36.737 \| good	1.442 \| good	15.124 \| good	0.197 \| good
2026-04-19T04:00:00.000Z	34 \| good	2.865 \| good	12.059 \| good	36.735 \| good	1.417 \| good	14.867 \| good	0.208 \| good
2026-04-19T05:00:00.000Z	33 \| good	2.01 \| good	8.156 \| good	35.716 \| good	1.391 \| good	14.611 \| good	0.219 \| good
2026-04-19T06:00:00.000Z	33 \| good	1.867 \| good	7.707 \| good	36.208 \| good	1.366 \| good	14.354 \| good	0.23 \| good
2026-04-19T07:00:00.000Z	35 \| good	1.306 \| good	5.452 \| good	37.775 \| good	1.24 \| good	13.48 \| good	0.223 \| good
2026-04-19T08:00:00.000Z	35 \| good	1.364 \| good	5.371 \| good	37.934 \| good	1.113 \| good	12.606 \| good	0.216 \| good
2026-04-19T09:00:00.000Z	34 \| good	1.164 \| good	4.959 \| good	37.351 \| good	0.987 \| good	11.732 \| good	0.21 \| good
2026-04-19T10:00:00.000Z	32 \| good	1.546 \| good	6.112 \| good	35.197 \| good	0.967 \| good	11.365 \| good	0.204 \| good
2026-04-19T11:00:00.000Z	31 \| good	1.81 \| good	7.647 \| good	33.281 \| good	0.946 \| good	10.998 \| good	0.199 \| good
2026-04-19T12:00:00.000Z	34 \| good	0.769 \| good	2.936 \| good	37.118 \| good	0.926 \| good	10.631 \| good	0.193 \| good
2026-04-19T13:00:00.000Z	25 \| good	3.232 \| good	13.731 \| good	27.027 \| good	0.981 \| good	9.93 \| good	0.19 \| good
2026-04-19T14:00:00.000Z	23 \| good	3.697 \| good	16.171 \| good	25.191 \| good	1.035 \| good	9.229 \| good	0.186 \| good
2026-04-19T15:00:00.000Z	28 \| good	4.249 \| good	18.154 \| good	30.166 \| good	1.089 \| good	8.528 \| good	0.183 \| good
2026-04-19T16:00:00.000Z	29 \| good	4.194 \| good	18.152 \| good	31.469 \| good	1.181 \| good	6.8 \| good	0.168 \| good
2026-04-19T17:00:00.000Z	30 \| good	4.582 \| good	19.901 \| good	32.036 \| good	1.273 \| good	5.072 \| good	0.152 \| good
2026-04-19T18:00:00.000Z	29 \| good	4.407 \| good	19.472 \| good	31.204 \| good	1.366 \| good	3.344 \| good	0.137 \| good
2026-04-19T19:00:00.000Z	31 \| good	4.934 \| good	21.274 \| good	33.715 \| good	1.288 \| good	2.896 \| good	0.134 \| good
2026-04-19T20:00:00.000Z	31 \| good	4.123 \| good	18.094 \| good	34.114 \| good	1.21 \| good	2.449 \| good	0.131 \| good
2026-04-19T21:00:00.000Z	31 \| good	3.713 \| good	16.486 \| good	33.825 \| good	1.133 \| good	2.001 \| good	0.128 \| good
2026-04-19T22:00:00.000Z	30 \| good	2.827 \| good	11.677 \| good	31.812 \| good	1.057 \| good	2.027 \| good	0.129 \| good
2026-04-19T23:00:00.000Z	30 \| good	2.25 \| good	8.884 \| good	32.205 \| good	0.981 \| good	2.053 \| good	0.129 \| good
2026-04-20T00:00:00.000Z	31 \| good	2.416 \| good	9.675 \| good	33.34 \| good	0.905 \| good	2.079 \| good	0.13 \| good
2026-04-20T01:00:00.000Z	31 \| good	1.92 \| good	8.191 \| good	33.766 \| good	0.882 \| good	2.805 \| good	0.134 \| good
2026-04-20T02:00:00.000Z	31 \| good	2.366 \| good	9.443 \| good	34.099 \| good	0.858 \| good	3.531 \| good	0.138 \| good
2026-04-20T03:00:00.000Z	29 \| good	2.269 \| good	9.277 \| good	30.961 \| good	0.835 \| good	4.257 \| good	0.143 \| good
2026-04-20T04:00:00.000Z	25 \| good	2.504 \| good	10.416 \| good	27.067 \| good	0.861 \| good	4.94 \| good	0.146 \| good
2026-04-20T05:00:00.000Z	26 \| good	1.996 \| good	8.277 \| good	27.678 \| good	0.888 \| good	5.623 \| good	0.149 \| good
2026-04-20T06:00:00.000Z	28 \| good	2.591 \| good	10.89 \| good	30.243 \| good	0.914 \| good	6.305 \| good	0.153 \| good
2026-04-20T07:00:00.000Z	30 \| good	2.741 \| good	11.737 \| good	31.632 \| good	0.875 \| good	6.742 \| good	0.156 \| good
2026-04-20T08:00:00.000Z	29 \| good	3.437 \| good	14.285 \| good	31.329 \| good	0.836 \| good	7.178 \| good	0.16 \| good
2026-04-20T09:00:00.000Z	27 \| good	3.531 \| good	15.317 \| good	29.383 \| good	0.796 \| good	7.614 \| good	0.163 \| good
2026-04-20T10:00:00.000Z	28 \| good	3.645 \| good	16.055 \| good	30.41 \| good	0.756 \| good	6.493 \| good	0.157 \| good
2026-04-20T11:00:00.000Z	29 \| good	3.837 \| good	17.028 \| good	30.697 \| good	0.716 \| good	5.372 \| good	0.151 \| good
2026-04-20T12:00:00.000Z	26 \| good	2.756 \| good	11.008 \| good	28.419 \| good	0.676 \| good	4.251 \| good	0.144 \| good
2026-04-20T13:00:00.000Z	22 \| good	2.459 \| good	10.181 \| good	23.743 \| good	0.677 \| good	4.221 \| good	0.144 \| good
2026-04-20T14:00:00.000Z	22 \| good	3.643 \| good	16.028 \| good	19.788 \| good	0.679 \| good	4.191 \| good	0.144 \| good
2026-04-20T15:00:00.000Z	27 \| good	4.854 \| good	21.305 \| good	22.878 \| good	0.68 \| good	4.161 \| good	0.144 \| good
2026-04-20T16:00:00.000Z	33 \| good	5.518 \| good	23.789 \| good	25.928 \| good	0.692 \| good	4.18 \| good	0.143 \| good
2026-04-20T17:00:00.000Z	27 \| good	4.909 \| good	21.522 \| good	28.363 \| good	0.705 \| good	4.198 \| good	0.143 \| good
2026-04-20T18:00:00.000Z	27 \| good	3.928 \| good	17.349 \| good	28.909 \| good	0.717 \| good	4.217 \| good	0.142 \| good
2026-04-20T19:00:00.000Z	30 \| good	2.506 \| good	10.531 \| good	32.224 \| good	0.621 \| good	3.481 \| good	0.137 \| good
2026-04-20T20:00:00.000Z	33 \| good	2.078 \| good	8.367 \| good	35.691 \| good	0.524 \| good	2.746 \| good	0.131 \| good
2026-04-20T21:00:00.000Z	33 \| good	1.533 \| good	6.192 \| good	36.498 \| good	0.428 \| good	2.01 \| good	0.126 \| good
2026-04-20T22:00:00.000Z	31 \| good	1.824 \| good	7.816 \| good	33.031 \| good	0.435 \| good	2.129 \| good	0.125 \| good
2026-04-20T23:00:00.000Z	29 \| good	2.526 \| good	10.33 \| good	31.304 \| good	0.442 \| good	2.248 \| good	0.125 \| good
2026-04-21T00:00:00.000Z	38 \| good	6.931 \| good	10.625 \| good	40.723 \| good	0.451 \| good	2.377 \| good	0.125 \| good
2026-04-21T01:00:00.000Z	29 \| good	3.449 \| good	15.3 \| good	30.99 \| good	0.52 \| good	3.166 \| good	0.128 \| good
2026-04-21T02:00:00.000Z	30 \| good	2.899 \| good	12.341 \| good	31.752 \| good	0.591 \| good	3.966 \| good	0.131 \| 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?