What is the sulfur dioxide (SO2) level in Waltham, Massachusetts at the moment?

Currently, Waltham, Massachusetts has a sulfur dioxide (SO2) concentration of 0.473 ppb.

What is the ozone (O3) level in Waltham, Massachusetts at the moment?

The current ozone (O3) level in Waltham, Massachusetts at the moment is 30.829 ppm.

What is the nitrogen dioxide (NO2) level in Waltham, Massachusetts at the moment?

Nitrogen dioxide (NO2) level in Waltham, Massachusetts at the moment is 22.536 ppb.

Live air quality index in Waltham, Massachusetts today

Q: What is the PM2.5 level in Waltham, Massachusetts at the moment?

PM2.5 levels in Waltham, Massachusetts are currently 8.253 μg/m3.

Q: What is the PM10 level in Waltham, Massachusetts at the moment?

The PM10 concentration in Waltham, Massachusetts is 31.209 μg/m3 at the moment.

Stay updated with real-time air quality in Waltham, Massachusetts 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

Waltham, Massachusetts

Last updated: ... (Local time)

Major air pollutants in Waltham, Massachusetts

Good

Fine

Moderate

Poor

Very poor

Hazardous

Particulate Matter_2.5 (PM_2.5)

8.25 μg/m³

12.1

35.5

55.5

250.5

500.5+

Particulate Matter₁₀ (PM₁₀)

31.21 μg/m³

155

255

425

605+

Ozone (O₃)

30.83 ppb

201

201+

Sulfur Dioxide (SO₂)

0.47 ppb

186

605

1005+

Nitrogen Dioxide (NO₂)

22.54 ppb

101

361

1250

2050+

Carbon Monoxide (CO)

0.38 ppm

4.5

9.5

12.5

230.5

50.5+

Pollen Level

Low

Waltham, Massachusetts

Get Live Pollen Counts

Waltham, Massachusetts

Scroll To Air Quality Map

Track live Waltham, Massachusetts air quality forecast and history

Time	AQI	PM_2.5	PM₁₀	O₃	SO₂	NO₂	CO
2025-12-27T00:00:00.000Z	27 \| good	5.06 \| good	23.915 \| good	20.073 \| good	0.417 \| good	13.531 \| good	0.332 \| good
2025-12-27T01:00:00.000Z	38 \| good	6.764 \| good	31.378 \| good	19.147 \| good	0.42 \| good	13.895 \| good	0.356 \| good
2025-12-27T02:00:00.000Z	33 \| good	6.377 \| good	31.422 \| good	21.783 \| good	0.407 \| good	12.949 \| good	0.345 \| good
2025-12-27T03:00:00.000Z	33 \| good	6.027 \| good	28.431 \| good	16.374 \| good	0.397 \| good	13.34 \| good	0.345 \| good
2025-12-27T04:00:00.000Z	33 \| good	5.602 \| good	21.428 \| good	23.231 \| good	0.398 \| good	17.395 \| good	0.345 \| good
2025-12-27T05:00:00.000Z	33 \| good	5.659 \| good	24.358 \| good	27.33 \| good	0.396 \| good	12.947 \| good	0.256 \| good
2025-12-27T06:00:00.000Z	27 \| good	5.071 \| good	22.264 \| good	26.13 \| good	0.389 \| good	10.887 \| good	0.233 \| good
2025-12-27T07:00:00.000Z	27 \| good	5.006 \| good	21.969 \| good	23.376 \| good	0.391 \| good	10.984 \| good	0.233 \| good
2025-12-27T08:00:00.000Z	27 \| good	5.228 \| good	21.385 \| good	26.202 \| good	0.394 \| good	14.09 \| good	0.233 \| good
2025-12-27T09:00:00.000Z	23 \| good	4.282 \| good	12.875 \| good	24.554 \| good	0.408 \| good	14.625 \| good	0.2 \| good
2025-12-27T10:00:00.000Z	24 \| good	3.876 \| good	13.655 \| good	26.409 \| good	0.416 \| good	13.726 \| good	0.211 \| good
2025-12-27T11:00:00.000Z	22 \| good	3.202 \| good	12.731 \| good	24.304 \| good	0.428 \| good	12.795 \| good	0.2 \| good
2025-12-27T12:00:00.000Z	28 \| good	3.535 \| good	16.122 \| good	30.41 \| good	0.415 \| good	12.199 \| good	0.2 \| good
2025-12-27T13:00:00.000Z	29 \| good	3.203 \| good	15.179 \| good	30.722 \| good	0.414 \| good	11.369 \| good	0.2 \| good
2025-12-27T14:00:00.000Z	28 \| good	3.173 \| good	12.721 \| good	30.366 \| good	0.401 \| good	11.785 \| good	0.254 \| good
2025-12-27T15:00:00.000Z	27 \| good	3.199 \| good	11.661 \| good	29.465 \| good	0.4 \| good	11.067 \| good	0.254 \| good
2025-12-27T16:00:00.000Z	27 \| good	3.106 \| good	13.948 \| good	29.371 \| good	0.387 \| good	10.146 \| good	0.233 \| good
2025-12-27T17:00:00.000Z	29 \| good	3.198 \| good	12.79 \| good	30.985 \| good	0.387 \| good	10.27 \| good	0.244 \| good
2025-12-27T18:00:00.000Z	28 \| good	3.173 \| good	14.499 \| good	29.859 \| good	0.411 \| good	9.509 \| good	0.233 \| good
2025-12-27T19:00:00.000Z	30 \| good	3.367 \| good	15.152 \| good	31.912 \| good	0.411 \| good	9.169 \| good	0.233 \| good
2025-12-27T20:00:00.000Z	31 \| good	3.301 \| good	11.856 \| good	33.328 \| good	0.401 \| good	9.085 \| good	0.233 \| good
2025-12-27T21:00:00.000Z	31 \| good	3.346 \| good	12.59 \| good	33.761 \| good	0.39 \| good	9.609 \| good	0.277 \| good
2025-12-27T22:00:00.000Z	35 \| good	4.817 \| good	37.522 \| good	31.211 \| good	0.337 \| good	11.271 \| good	0.32 \| good
2025-12-27T23:00:00.000Z	36 \| good	6.301 \| good	38.965 \| good	27.018 \| good	0.402 \| good	18.009 \| good	0.35 \| good
2025-12-28T00:00:00.000Z	33 \| good	5.855 \| good	22.677 \| good	25.301 \| good	0.397 \| good	17.864 \| good	0.427 \| good
2025-12-28T01:00:00.000Z	49 \| good	8.962 \| good	38.909 \| good	23.108 \| good	0.375 \| good	24.897 \| good	0.548 \| good
2025-12-28T02:00:00.000Z	38 \| good	7.267 \| good	23.236 \| good	16.25 \| good	0.427 \| good	24.66 \| good	0.584 \| good
2025-12-28T03:00:00.000Z	56 \| moderate	12.372 \| fine	56.245 \| fine	12.169 \| good	0.835 \| good	27.911 \| good	0.295 \| good
2025-12-28T04:00:00.000Z	49 \| good	8.954 \| good	30.198 \| good	18.07 \| good	0.436 \| good	20.784 \| good	0.407 \| good
2025-12-28T05:00:00.000Z	52 \| moderate	10.491 \| good	43.462 \| good	16.017 \| good	0.463 \| good	20.794 \| good	0.396 \| good
2025-12-28T06:00:00.000Z	54 \| moderate	10.725 \| good	50.261 \| good	17.956 \| good	0.41 \| good	15.606 \| good	0.396 \| good
2025-12-28T07:00:00.000Z	54 \| moderate	10.85 \| good	53.146 \| good	14.596 \| good	0.398 \| good	16.524 \| good	0.376 \| good
2025-12-28T08:00:00.000Z	54 \| moderate	10.814 \| good	45.515 \| good	19.827 \| good	0.387 \| good	27.382 \| good	0.342 \| good
2025-12-28T09:00:00.000Z	53 \| moderate	10.043 \| good	59.031 \| fine	15.918 \| good	0.465 \| good	21.765 \| good	0.406 \| good
2025-12-28T10:00:00.000Z	49 \| good	9.434 \| good	36.566 \| good	6.995 \| good	0.512 \| good	17.509 \| good	0.417 \| good
2025-12-28T11:00:00.000Z	38 \| good	7.29 \| good	27.515 \| good	12.819 \| good	0.528 \| good	17.498 \| good	0.417 \| good
2025-12-28T12:00:00.000Z	38 \| good	6.993 \| good	27.145 \| good	12.689 \| good	0.572 \| good	25.305 \| good	0.416 \| good
2025-12-28T13:00:00.000Z	54 \| moderate	10.566 \| good	38.62 \| good	16.654 \| good	0.574 \| good	28.382 \| good	0.46 \| good
2025-12-28T14:00:00.000Z	54 \| moderate	10.719 \| good	25.966 \| good	18.745 \| good	0.432 \| good	25.858 \| good	0.434 \| good
2025-12-28T15:00:00.000Z	38 \| good	6.558 \| good	26.254 \| good	15.074 \| good	0.489 \| good	19.06 \| good	0.35 \| good
2025-12-28T16:00:00.000Z	52 \| moderate	6.923 \| good	56.941 \| fine	16.521 \| good	0.484 \| good	16.434 \| good	0.329 \| good
2025-12-28T17:00:00.000Z	27 \| good	5.318 \| good	21.11 \| good	23.997 \| good	0.463 \| good	13.944 \| good	0.296 \| good
2025-12-28T18:00:00.000Z	46 \| good	4.829 \| good	50.199 \| good	30.825 \| good	0.478 \| good	12.055 \| good	0.296 \| good
2025-12-28T19:00:00.000Z	33 \| good	5.637 \| good	20.473 \| good	30.453 \| good	0.446 \| good	13.428 \| good	0.296 \| good
2025-12-28T20:00:00.000Z	33 \| good	6.446 \| good	31.548 \| good	30.393 \| good	0.437 \| good	14.681 \| good	0.342 \| good
2025-12-28T21:00:00.000Z	38 \| good	7.183 \| good	40.894 \| good	28.099 \| good	0.464 \| good	16.491 \| good	0.362 \| good
2025-12-28T22:00:00.000Z	44 \| good	8.247 \| good	31.246 \| good	29.358 \| good	0.473 \| good	22.554 \| good	0.372 \| good
2025-12-28T23:00:00.000Z	44 \| good	8.253 \| good	31.209 \| good	30.829 \| good	0.473 \| good	22.536 \| good	0.377 \| good
2025-12-29T00:00:00.000Z	60 \| moderate	14.065 \| fine	63.07 \| fine	15.418 \| good	1.349 \| good	29.089 \| good	0.312 \| good
2025-12-29T01:00:00.000Z	62 \| moderate	14.808 \| fine	66.206 \| fine	16.724 \| good	1.566 \| good	27.378 \| good	0.297 \| good
2025-12-29T02:00:00.000Z	62 \| moderate	15.289 \| fine	69 \| fine	15.682 \| good	1.784 \| good	25.667 \| good	0.283 \| good
2025-12-29T03:00:00.000Z	67 \| moderate	17.615 \| fine	78.191 \| fine	10.111 \| good	2.001 \| good	23.956 \| good	0.268 \| good
2025-12-29T04:00:00.000Z	71 \| moderate	19.643 \| fine	86.618 \| fine	7.204 \| good	1.857 \| good	23.253 \| good	0.256 \| good
2025-12-29T05:00:00.000Z	69 \| moderate	18.916 \| fine	83.687 \| fine	8.085 \| good	1.712 \| good	22.549 \| good	0.245 \| good
2025-12-29T06:00:00.000Z	62 \| moderate	15.389 \| fine	68.744 \| fine	13.142 \| good	1.568 \| good	21.845 \| good	0.233 \| good
2025-12-29T07:00:00.000Z	52 \| moderate	9.693 \| good	43.301 \| good	21.11 \| good	1.212 \| good	16.116 \| good	0.205 \| good
2025-12-29T08:00:00.000Z	38 \| good	6.982 \| good	30.91 \| good	23.494 \| good	0.857 \| good	10.386 \| good	0.177 \| good
2025-12-29T09:00:00.000Z	33 \| good	5.686 \| good	24.664 \| good	22.048 \| good	0.501 \| good	4.657 \| good	0.149 \| good
2025-12-29T10:00:00.000Z	22 \| good	3.622 \| good	15.273 \| good	20.485 \| good	0.549 \| good	5.655 \| good	0.153 \| good
2025-12-29T11:00:00.000Z	19 \| good	2.708 \| good	11.238 \| good	20.612 \| good	0.596 \| good	6.654 \| good	0.158 \| good
2025-12-29T12:00:00.000Z	20 \| good	2.492 \| good	10.378 \| good	22.02 \| good	0.644 \| good	7.652 \| good	0.162 \| good
2025-12-29T13:00:00.000Z	19 \| good	2.576 \| good	10.446 \| good	21.069 \| good	0.83 \| good	8.51 \| good	0.171 \| good
2025-12-29T14:00:00.000Z	19 \| good	3.358 \| good	14.71 \| good	20.303 \| good	1.016 \| good	9.368 \| good	0.181 \| good
2025-12-29T15:00:00.000Z	22 \| good	4.097 \| good	17.898 \| good	19.098 \| good	1.202 \| good	10.225 \| good	0.191 \| good
2025-12-29T16:00:00.000Z	22 \| good	3.551 \| good	15.6 \| good	23.501 \| good	1.145 \| good	9.754 \| good	0.189 \| good
2025-12-29T17:00:00.000Z	27 \| good	5.43 \| good	23.038 \| good	24.198 \| good	1.089 \| good	9.283 \| good	0.187 \| good
2025-12-29T18:00:00.000Z	38 \| good	6.717 \| good	29.992 \| good	24.59 \| good	1.032 \| good	8.812 \| good	0.186 \| good
2025-12-29T19:00:00.000Z	44 \| good	8.291 \| good	36.192 \| good	22.722 \| good	1.103 \| good	10.111 \| good	0.192 \| good
2025-12-29T20:00:00.000Z	33 \| good	5.646 \| good	24.312 \| good	29.372 \| good	1.174 \| good	11.41 \| good	0.198 \| good
2025-12-29T21:00:00.000Z	33 \| good	3.683 \| good	15.838 \| good	36.296 \| good	1.244 \| good	12.709 \| good	0.204 \| good
2025-12-29T22:00:00.000Z	31 \| good	4.608 \| good	20.067 \| good	34.378 \| good	1.405 \| good	11.784 \| good	0.199 \| good
2025-12-29T23:00:00.000Z	33 \| good	6.133 \| good	27.279 \| good	31.638 \| good	1.565 \| good	10.858 \| good	0.194 \| good
2025-12-30T00:00:00.000Z	44 \| good	7.872 \| good	34.485 \| good	29.328 \| good	1.725 \| good	9.933 \| good	0.188 \| good
2025-12-30T01:00:00.000Z	44 \| good	8.041 \| good	35.352 \| good	27.277 \| good	1.396 \| good	8.075 \| good	0.185 \| good
2025-12-30T02:00:00.000Z	33 \| good	5.85 \| good	25.513 \| good	24.818 \| good	1.067 \| good	6.217 \| good	0.181 \| good
2025-12-30T03:00:00.000Z	22 \| good	4.405 \| good	19.078 \| good	23.202 \| good	0.738 \| good	4.359 \| good	0.177 \| good
2025-12-30T04:00:00.000Z	22 \| good	3.945 \| good	17.109 \| good	22.941 \| good	0.658 \| good	3.787 \| good	0.17 \| good
2025-12-30T05:00:00.000Z	23 \| good	3.188 \| good	13.707 \| good	25.439 \| good	0.577 \| good	3.215 \| good	0.162 \| good
2025-12-30T06:00:00.000Z	27 \| good	2.472 \| good	10.067 \| good	28.947 \| good	0.496 \| good	2.642 \| good	0.154 \| good
2025-12-30T07:00:00.000Z	28 \| good	1.236 \| good	5 \| good	29.925 \| good	0.477 \| good	2.419 \| good	0.149 \| good
2025-12-30T08:00:00.000Z	28 \| good	0.166 \| good	0.188 \| good	30.324 \| good	0.458 \| good	2.196 \| good	0.145 \| good
2025-12-30T09:00:00.000Z	29 \| good	0.16 \| good	0 \| good	30.947 \| good	0.438 \| good	1.972 \| good	0.14 \| good
2025-12-30T10:00:00.000Z	28 \| good	0.246 \| good	0.907 \| good	30.358 \| good	0.468 \| good	2.689 \| good	0.144 \| good
2025-12-30T11:00:00.000Z	27 \| good	0.473 \| good	1.771 \| good	28.868 \| good	0.497 \| good	3.405 \| good	0.147 \| good
2025-12-30T12:00:00.000Z	26 \| good	0.588 \| good	2.013 \| good	27.772 \| good	0.526 \| good	4.122 \| good	0.151 \| good
2025-12-30T13:00:00.000Z	26 \| good	0.307 \| good	0.976 \| good	28.274 \| good	0.461 \| good	3.423 \| good	0.147 \| good
2025-12-30T14:00:00.000Z	27 \| good	0.193 \| good	0.454 \| good	28.898 \| good	0.395 \| good	2.723 \| good	0.143 \| good
2025-12-30T15:00:00.000Z	28 \| good	0.284 \| good	0.987 \| good	29.86 \| good	0.33 \| good	2.024 \| good	0.139 \| good
2025-12-30T16:00:00.000Z	29 \| good	0.764 \| good	2.969 \| good	31.391 \| good	0.32 \| good	1.907 \| good	0.137 \| good
2025-12-30T17:00:00.000Z	30 \| good	1.175 \| good	5 \| good	32.255 \| good	0.311 \| good	1.791 \| good	0.136 \| good
2025-12-30T18:00:00.000Z	31 \| good	0.834 \| good	3.055 \| good	33.011 \| good	0.301 \| good	1.674 \| good	0.135 \| good
2025-12-30T19:00:00.000Z	31 \| good	0.908 \| good	3.582 \| good	33.449 \| good	0.312 \| good	2.027 \| good	0.136 \| good
2025-12-30T20:00:00.000Z	32 \| good	0.627 \| good	2.092 \| good	35.084 \| good	0.323 \| good	2.381 \| good	0.137 \| good
2025-12-30T21:00:00.000Z	33 \| good	1.199 \| good	4.864 \| good	35.771 \| good	0.333 \| good	2.735 \| good	0.138 \| good
2025-12-30T22:00:00.000Z	31 \| good	1.707 \| good	6.979 \| good	33.396 \| good	0.392 \| good	3.211 \| good	0.14 \| good
2025-12-30T23:00:00.000Z	31 \| good	1.97 \| good	8.117 \| good	33.58 \| good	0.451 \| good	3.688 \| good	0.141 \| good

Waltham

Get reliable air quality data to drive your business

Waltham, Massachusetts air quality map: Stay updated on AQI near you

0.43ppm

How accurate is Massachusetts, USA air quality data?

Air quality and pollutant data for Massachusetts, USA are sourced from ground-based monitors and satellites, adhering to US EPA standards. Machine learning and advanced algorithms enhance the data by incorporating local variables like traffic and population density, ensuring high accuracy and dependability.

Source: Ambee Data Sources

Air quality levels in US

Check live rankings of places in the USA affected by air pollution.

View Polluted Cities

Check live rankings of places in the USA with the cleanest air.

View Clean Cities

Frequently asked questions

How often is air quality information updated for Waltham, Massachusetts?

The air quality information for Waltham, Massachusetts is updated every hour for accuracy.

What time in the last 24 hours was the air quality in Waltham, Massachusetts at its worst?

In the past 24 hours, the air quality in Waltham, Massachusetts was at its worst at 03:00:00 on 2025-12-28.

When did Waltham, Massachusetts experience the best air quality in the last 24 hours?

In the last 24 hours, the best air quality in Waltham, Massachusetts was observed at 05:00:00 on 2025-12-28.

What is the AQI in Waltham, Massachusetts right now?

As of now, the AQI in Waltham, Massachusetts is 44, indicating Good conditions.

What is the most common type of pollution in Waltham, Massachusetts?

Waltham, Massachusetts air has the highest levels of PM2.5.

What should I do in case of poor air quality in Waltham, Massachusetts?

Poor air quality in Waltham, Massachusetts means it's advisable to stay indoors and wear a mask for your protection.

What is the PM_2.5 level in Waltham, Massachusetts at the moment?

PM_2.5 levels in Waltham, Massachusetts are currently 8.253 μg/m³.

What is the PM₁₀ level in Waltham, Massachusetts at the moment?

The PM₁₀ concentration in Waltham, Massachusetts is 31.209 μg/m³ at the moment.

What is the carbon monoxide (CO) level in Waltham, Massachusetts at the moment?

The current carbon monoxide (CO) concentration in Waltham, Massachusetts is 0.377 ppm.

What is the sulfur dioxide (SO₂) level in Waltham, Massachusetts at the moment?

Currently, Waltham, Massachusetts has a sulfur dioxide (SO₂) concentration of 0.473 ppb.

What is the ozone (O₃) level in Waltham, Massachusetts at the moment?

The current ozone (O₃) level in Waltham, Massachusetts at the moment is 30.829 ppm.

What is the nitrogen dioxide (NO₂) level in Waltham, Massachusetts at the moment?

Nitrogen dioxide (NO₂) level in Waltham, Massachusetts at the moment is 22.536 ppb.

Certified

APIs

Refund Policy

Historical Climate Data

Terms & Conditions

Refund Policy

Terms & Conditions

Time	AQI	PM_2.5	PM₁₀	O₃	SO₂	NO₂	CO
2025-12-27T00:00:00.000Z	27 \| good	5.06 \| good	23.915 \| good	20.073 \| good	0.417 \| good	13.531 \| good	0.332 \| good
2025-12-27T01:00:00.000Z	38 \| good	6.764 \| good	31.378 \| good	19.147 \| good	0.42 \| good	13.895 \| good	0.356 \| good
2025-12-27T02:00:00.000Z	33 \| good	6.377 \| good	31.422 \| good	21.783 \| good	0.407 \| good	12.949 \| good	0.345 \| good
2025-12-27T03:00:00.000Z	33 \| good	6.027 \| good	28.431 \| good	16.374 \| good	0.397 \| good	13.34 \| good	0.345 \| good
2025-12-27T04:00:00.000Z	33 \| good	5.602 \| good	21.428 \| good	23.231 \| good	0.398 \| good	17.395 \| good	0.345 \| good
2025-12-27T05:00:00.000Z	33 \| good	5.659 \| good	24.358 \| good	27.33 \| good	0.396 \| good	12.947 \| good	0.256 \| good
2025-12-27T06:00:00.000Z	27 \| good	5.071 \| good	22.264 \| good	26.13 \| good	0.389 \| good	10.887 \| good	0.233 \| good
2025-12-27T07:00:00.000Z	27 \| good	5.006 \| good	21.969 \| good	23.376 \| good	0.391 \| good	10.984 \| good	0.233 \| good
2025-12-27T08:00:00.000Z	27 \| good	5.228 \| good	21.385 \| good	26.202 \| good	0.394 \| good	14.09 \| good	0.233 \| good
2025-12-27T09:00:00.000Z	23 \| good	4.282 \| good	12.875 \| good	24.554 \| good	0.408 \| good	14.625 \| good	0.2 \| good
2025-12-27T10:00:00.000Z	24 \| good	3.876 \| good	13.655 \| good	26.409 \| good	0.416 \| good	13.726 \| good	0.211 \| good
2025-12-27T11:00:00.000Z	22 \| good	3.202 \| good	12.731 \| good	24.304 \| good	0.428 \| good	12.795 \| good	0.2 \| good
2025-12-27T12:00:00.000Z	28 \| good	3.535 \| good	16.122 \| good	30.41 \| good	0.415 \| good	12.199 \| good	0.2 \| good
2025-12-27T13:00:00.000Z	29 \| good	3.203 \| good	15.179 \| good	30.722 \| good	0.414 \| good	11.369 \| good	0.2 \| good
2025-12-27T14:00:00.000Z	28 \| good	3.173 \| good	12.721 \| good	30.366 \| good	0.401 \| good	11.785 \| good	0.254 \| good
2025-12-27T15:00:00.000Z	27 \| good	3.199 \| good	11.661 \| good	29.465 \| good	0.4 \| good	11.067 \| good	0.254 \| good
2025-12-27T16:00:00.000Z	27 \| good	3.106 \| good	13.948 \| good	29.371 \| good	0.387 \| good	10.146 \| good	0.233 \| good
2025-12-27T17:00:00.000Z	29 \| good	3.198 \| good	12.79 \| good	30.985 \| good	0.387 \| good	10.27 \| good	0.244 \| good
2025-12-27T18:00:00.000Z	28 \| good	3.173 \| good	14.499 \| good	29.859 \| good	0.411 \| good	9.509 \| good	0.233 \| good
2025-12-27T19:00:00.000Z	30 \| good	3.367 \| good	15.152 \| good	31.912 \| good	0.411 \| good	9.169 \| good	0.233 \| good
2025-12-27T20:00:00.000Z	31 \| good	3.301 \| good	11.856 \| good	33.328 \| good	0.401 \| good	9.085 \| good	0.233 \| good
2025-12-27T21:00:00.000Z	31 \| good	3.346 \| good	12.59 \| good	33.761 \| good	0.39 \| good	9.609 \| good	0.277 \| good
2025-12-27T22:00:00.000Z	35 \| good	4.817 \| good	37.522 \| good	31.211 \| good	0.337 \| good	11.271 \| good	0.32 \| good
2025-12-27T23:00:00.000Z	36 \| good	6.301 \| good	38.965 \| good	27.018 \| good	0.402 \| good	18.009 \| good	0.35 \| good
2025-12-28T00:00:00.000Z	33 \| good	5.855 \| good	22.677 \| good	25.301 \| good	0.397 \| good	17.864 \| good	0.427 \| good
2025-12-28T01:00:00.000Z	49 \| good	8.962 \| good	38.909 \| good	23.108 \| good	0.375 \| good	24.897 \| good	0.548 \| good
2025-12-28T02:00:00.000Z	38 \| good	7.267 \| good	23.236 \| good	16.25 \| good	0.427 \| good	24.66 \| good	0.584 \| good
2025-12-28T03:00:00.000Z	56 \| moderate	12.372 \| fine	56.245 \| fine	12.169 \| good	0.835 \| good	27.911 \| good	0.295 \| good
2025-12-28T04:00:00.000Z	49 \| good	8.954 \| good	30.198 \| good	18.07 \| good	0.436 \| good	20.784 \| good	0.407 \| good
2025-12-28T05:00:00.000Z	52 \| moderate	10.491 \| good	43.462 \| good	16.017 \| good	0.463 \| good	20.794 \| good	0.396 \| good
2025-12-28T06:00:00.000Z	54 \| moderate	10.725 \| good	50.261 \| good	17.956 \| good	0.41 \| good	15.606 \| good	0.396 \| good
2025-12-28T07:00:00.000Z	54 \| moderate	10.85 \| good	53.146 \| good	14.596 \| good	0.398 \| good	16.524 \| good	0.376 \| good
2025-12-28T08:00:00.000Z	54 \| moderate	10.814 \| good	45.515 \| good	19.827 \| good	0.387 \| good	27.382 \| good	0.342 \| good
2025-12-28T09:00:00.000Z	53 \| moderate	10.043 \| good	59.031 \| fine	15.918 \| good	0.465 \| good	21.765 \| good	0.406 \| good
2025-12-28T10:00:00.000Z	49 \| good	9.434 \| good	36.566 \| good	6.995 \| good	0.512 \| good	17.509 \| good	0.417 \| good
2025-12-28T11:00:00.000Z	38 \| good	7.29 \| good	27.515 \| good	12.819 \| good	0.528 \| good	17.498 \| good	0.417 \| good
2025-12-28T12:00:00.000Z	38 \| good	6.993 \| good	27.145 \| good	12.689 \| good	0.572 \| good	25.305 \| good	0.416 \| good
2025-12-28T13:00:00.000Z	54 \| moderate	10.566 \| good	38.62 \| good	16.654 \| good	0.574 \| good	28.382 \| good	0.46 \| good
2025-12-28T14:00:00.000Z	54 \| moderate	10.719 \| good	25.966 \| good	18.745 \| good	0.432 \| good	25.858 \| good	0.434 \| good
2025-12-28T15:00:00.000Z	38 \| good	6.558 \| good	26.254 \| good	15.074 \| good	0.489 \| good	19.06 \| good	0.35 \| good
2025-12-28T16:00:00.000Z	52 \| moderate	6.923 \| good	56.941 \| fine	16.521 \| good	0.484 \| good	16.434 \| good	0.329 \| good
2025-12-28T17:00:00.000Z	27 \| good	5.318 \| good	21.11 \| good	23.997 \| good	0.463 \| good	13.944 \| good	0.296 \| good
2025-12-28T18:00:00.000Z	46 \| good	4.829 \| good	50.199 \| good	30.825 \| good	0.478 \| good	12.055 \| good	0.296 \| good
2025-12-28T19:00:00.000Z	33 \| good	5.637 \| good	20.473 \| good	30.453 \| good	0.446 \| good	13.428 \| good	0.296 \| good
2025-12-28T20:00:00.000Z	33 \| good	6.446 \| good	31.548 \| good	30.393 \| good	0.437 \| good	14.681 \| good	0.342 \| good
2025-12-28T21:00:00.000Z	38 \| good	7.183 \| good	40.894 \| good	28.099 \| good	0.464 \| good	16.491 \| good	0.362 \| good
2025-12-28T22:00:00.000Z	44 \| good	8.247 \| good	31.246 \| good	29.358 \| good	0.473 \| good	22.554 \| good	0.372 \| good
2025-12-28T23:00:00.000Z	44 \| good	8.253 \| good	31.209 \| good	30.829 \| good	0.473 \| good	22.536 \| good	0.377 \| good
2025-12-29T00:00:00.000Z	60 \| moderate	14.065 \| fine	63.07 \| fine	15.418 \| good	1.349 \| good	29.089 \| good	0.312 \| good
2025-12-29T01:00:00.000Z	62 \| moderate	14.808 \| fine	66.206 \| fine	16.724 \| good	1.566 \| good	27.378 \| good	0.297 \| good
2025-12-29T02:00:00.000Z	62 \| moderate	15.289 \| fine	69 \| fine	15.682 \| good	1.784 \| good	25.667 \| good	0.283 \| good
2025-12-29T03:00:00.000Z	67 \| moderate	17.615 \| fine	78.191 \| fine	10.111 \| good	2.001 \| good	23.956 \| good	0.268 \| good
2025-12-29T04:00:00.000Z	71 \| moderate	19.643 \| fine	86.618 \| fine	7.204 \| good	1.857 \| good	23.253 \| good	0.256 \| good
2025-12-29T05:00:00.000Z	69 \| moderate	18.916 \| fine	83.687 \| fine	8.085 \| good	1.712 \| good	22.549 \| good	0.245 \| good
2025-12-29T06:00:00.000Z	62 \| moderate	15.389 \| fine	68.744 \| fine	13.142 \| good	1.568 \| good	21.845 \| good	0.233 \| good
2025-12-29T07:00:00.000Z	52 \| moderate	9.693 \| good	43.301 \| good	21.11 \| good	1.212 \| good	16.116 \| good	0.205 \| good
2025-12-29T08:00:00.000Z	38 \| good	6.982 \| good	30.91 \| good	23.494 \| good	0.857 \| good	10.386 \| good	0.177 \| good
2025-12-29T09:00:00.000Z	33 \| good	5.686 \| good	24.664 \| good	22.048 \| good	0.501 \| good	4.657 \| good	0.149 \| good
2025-12-29T10:00:00.000Z	22 \| good	3.622 \| good	15.273 \| good	20.485 \| good	0.549 \| good	5.655 \| good	0.153 \| good
2025-12-29T11:00:00.000Z	19 \| good	2.708 \| good	11.238 \| good	20.612 \| good	0.596 \| good	6.654 \| good	0.158 \| good
2025-12-29T12:00:00.000Z	20 \| good	2.492 \| good	10.378 \| good	22.02 \| good	0.644 \| good	7.652 \| good	0.162 \| good
2025-12-29T13:00:00.000Z	19 \| good	2.576 \| good	10.446 \| good	21.069 \| good	0.83 \| good	8.51 \| good	0.171 \| good
2025-12-29T14:00:00.000Z	19 \| good	3.358 \| good	14.71 \| good	20.303 \| good	1.016 \| good	9.368 \| good	0.181 \| good
2025-12-29T15:00:00.000Z	22 \| good	4.097 \| good	17.898 \| good	19.098 \| good	1.202 \| good	10.225 \| good	0.191 \| good
2025-12-29T16:00:00.000Z	22 \| good	3.551 \| good	15.6 \| good	23.501 \| good	1.145 \| good	9.754 \| good	0.189 \| good
2025-12-29T17:00:00.000Z	27 \| good	5.43 \| good	23.038 \| good	24.198 \| good	1.089 \| good	9.283 \| good	0.187 \| good
2025-12-29T18:00:00.000Z	38 \| good	6.717 \| good	29.992 \| good	24.59 \| good	1.032 \| good	8.812 \| good	0.186 \| good
2025-12-29T19:00:00.000Z	44 \| good	8.291 \| good	36.192 \| good	22.722 \| good	1.103 \| good	10.111 \| good	0.192 \| good
2025-12-29T20:00:00.000Z	33 \| good	5.646 \| good	24.312 \| good	29.372 \| good	1.174 \| good	11.41 \| good	0.198 \| good
2025-12-29T21:00:00.000Z	33 \| good	3.683 \| good	15.838 \| good	36.296 \| good	1.244 \| good	12.709 \| good	0.204 \| good
2025-12-29T22:00:00.000Z	31 \| good	4.608 \| good	20.067 \| good	34.378 \| good	1.405 \| good	11.784 \| good	0.199 \| good
2025-12-29T23:00:00.000Z	33 \| good	6.133 \| good	27.279 \| good	31.638 \| good	1.565 \| good	10.858 \| good	0.194 \| good
2025-12-30T00:00:00.000Z	44 \| good	7.872 \| good	34.485 \| good	29.328 \| good	1.725 \| good	9.933 \| good	0.188 \| good
2025-12-30T01:00:00.000Z	44 \| good	8.041 \| good	35.352 \| good	27.277 \| good	1.396 \| good	8.075 \| good	0.185 \| good
2025-12-30T02:00:00.000Z	33 \| good	5.85 \| good	25.513 \| good	24.818 \| good	1.067 \| good	6.217 \| good	0.181 \| good
2025-12-30T03:00:00.000Z	22 \| good	4.405 \| good	19.078 \| good	23.202 \| good	0.738 \| good	4.359 \| good	0.177 \| good
2025-12-30T04:00:00.000Z	22 \| good	3.945 \| good	17.109 \| good	22.941 \| good	0.658 \| good	3.787 \| good	0.17 \| good
2025-12-30T05:00:00.000Z	23 \| good	3.188 \| good	13.707 \| good	25.439 \| good	0.577 \| good	3.215 \| good	0.162 \| good
2025-12-30T06:00:00.000Z	27 \| good	2.472 \| good	10.067 \| good	28.947 \| good	0.496 \| good	2.642 \| good	0.154 \| good
2025-12-30T07:00:00.000Z	28 \| good	1.236 \| good	5 \| good	29.925 \| good	0.477 \| good	2.419 \| good	0.149 \| good
2025-12-30T08:00:00.000Z	28 \| good	0.166 \| good	0.188 \| good	30.324 \| good	0.458 \| good	2.196 \| good	0.145 \| good
2025-12-30T09:00:00.000Z	29 \| good	0.16 \| good	0 \| good	30.947 \| good	0.438 \| good	1.972 \| good	0.14 \| good
2025-12-30T10:00:00.000Z	28 \| good	0.246 \| good	0.907 \| good	30.358 \| good	0.468 \| good	2.689 \| good	0.144 \| good
2025-12-30T11:00:00.000Z	27 \| good	0.473 \| good	1.771 \| good	28.868 \| good	0.497 \| good	3.405 \| good	0.147 \| good
2025-12-30T12:00:00.000Z	26 \| good	0.588 \| good	2.013 \| good	27.772 \| good	0.526 \| good	4.122 \| good	0.151 \| good
2025-12-30T13:00:00.000Z	26 \| good	0.307 \| good	0.976 \| good	28.274 \| good	0.461 \| good	3.423 \| good	0.147 \| good
2025-12-30T14:00:00.000Z	27 \| good	0.193 \| good	0.454 \| good	28.898 \| good	0.395 \| good	2.723 \| good	0.143 \| good
2025-12-30T15:00:00.000Z	28 \| good	0.284 \| good	0.987 \| good	29.86 \| good	0.33 \| good	2.024 \| good	0.139 \| good
2025-12-30T16:00:00.000Z	29 \| good	0.764 \| good	2.969 \| good	31.391 \| good	0.32 \| good	1.907 \| good	0.137 \| good
2025-12-30T17:00:00.000Z	30 \| good	1.175 \| good	5 \| good	32.255 \| good	0.311 \| good	1.791 \| good	0.136 \| good
2025-12-30T18:00:00.000Z	31 \| good	0.834 \| good	3.055 \| good	33.011 \| good	0.301 \| good	1.674 \| good	0.135 \| good
2025-12-30T19:00:00.000Z	31 \| good	0.908 \| good	3.582 \| good	33.449 \| good	0.312 \| good	2.027 \| good	0.136 \| good
2025-12-30T20:00:00.000Z	32 \| good	0.627 \| good	2.092 \| good	35.084 \| good	0.323 \| good	2.381 \| good	0.137 \| good
2025-12-30T21:00:00.000Z	33 \| good	1.199 \| good	4.864 \| good	35.771 \| good	0.333 \| good	2.735 \| good	0.138 \| good
2025-12-30T22:00:00.000Z	31 \| good	1.707 \| good	6.979 \| good	33.396 \| good	0.392 \| good	3.211 \| good	0.14 \| good
2025-12-30T23:00:00.000Z	31 \| good	1.97 \| good	8.117 \| good	33.58 \| good	0.451 \| good	3.688 \| good	0.141 \| good

Live air quality index in Waltham, Massachusetts today

Major air pollutants in Waltham, Massachusetts

Particulate Matter2.5 (PM2.5)

Particulate Matter10 (PM10)

Ozone (O3)

Sulfur Dioxide (SO2)

Nitrogen Dioxide (NO2)

Carbon Monoxide (CO)

Track live Waltham, Massachusetts air quality forecast and history

Get reliable air quality data to drive your business

Waltham, Massachusetts air quality map: Stay updated on AQI near you

Air quality in nearby cities

Watertown, Massachusetts

Newton, Massachusetts

Belmont, Massachusetts

Weston, Massachusetts

Wellesley, Massachusetts

Arlington, Massachusetts

How accurate is Massachusetts, USA air quality data?

Air quality levels in US

Frequently asked questions

How often is air quality information updated for Waltham, Massachusetts?

What time in the last 24 hours was the air quality in Waltham, Massachusetts at its worst?

When did Waltham, Massachusetts experience the best air quality in the last 24 hours?

What is the AQI in Waltham, Massachusetts right now?

What is the most common type of pollution in Waltham, Massachusetts?

What should I do in case of poor air quality in Waltham, Massachusetts?

What is the PM2.5 level in Waltham, Massachusetts at the moment?

What is the PM10 level in Waltham, Massachusetts at the moment?

What is the carbon monoxide (CO) level in Waltham, Massachusetts at the moment?

What is the sulfur dioxide (SO2) level in Waltham, Massachusetts at the moment?

What is the ozone (O3) level in Waltham, Massachusetts at the moment?

What is the nitrogen dioxide (NO2) level in Waltham, Massachusetts at the moment?

Particulate Matter_2.5 (PM_2.5)

Particulate Matter₁₀ (PM₁₀)

Ozone (O₃)

Sulfur Dioxide (SO₂)

Nitrogen Dioxide (NO₂)

What is the PM_2.5 level in Waltham, Massachusetts at the moment?

What is the PM₁₀ level in Waltham, Massachusetts at the moment?

What is the sulfur dioxide (SO₂) level in Waltham, Massachusetts at the moment?

What is the ozone (O₃) level in Waltham, Massachusetts at the moment?

What is the nitrogen dioxide (NO₂) level in Waltham, Massachusetts at the moment?