A
APIs Score

Purple Air API

Science & Math / No Auth Required Beginner HTTPS
Free to Use
82 A
Metadata Score 0 50 100 Metadata estimate · not endpoint-tested
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Overview

Purple Air gives you access to real-time air quality data from a global network of community-owned sensors. You can query sensor readings, location data, and historical air quality metrics without any authentication. It is a great starting point for environmental monitoring projects or building local air quality dashboards.

Beginner Tip

PurpleAir sensors report PM2.5 particulate matter — query by sensor ID or bounding box to get readings for a specific area. Note that the newer API v1 (api.purpleair.com) now requires an API key, so check which version you are targeting.

Available Data

The kind of data this API exposes, based on its documentation. We could not call the endpoint to confirm the exact field names.

Purple Air data via REST API

Example Response

Illustrative shape only — we were not able to call this endpoint (it requires credentials or exposes no public sample URL), so the fields below show the kind of data this API returns rather than a recorded response.

JSON Response · Illustrative 
{
  "status": "success",
  "data": {
    "result": "Data from Purple Air",
    "description": "Real Time Air Quality Monitoring",
    "timestamp": "2025-01-15T10:00:00Z"
  }
}

Field Reference

sensor_index Unique identifier for each PurpleAir sensor.
name Human-readable label given to the sensor by its owner.
pm2.5_atm PM2.5 particulate matter reading in micrograms per cubic meter, corrected for atmospheric pressure.
latitude Latitude coordinate of the sensor location.
longitude Longitude coordinate of the sensor location.
last_seen Unix timestamp of the most recent data upload from this sensor.

Implementation Example

Calls a real endpoint of this API. Replace any placeholder credentials with your own key.

Request 
const url = "https://api.purpleair.com/v1/sensors?fields=name,pm2.5";
const response = await fetch(url);
if (!response.ok) throw new Error(`Request failed: ${response.status}`);
const data = await response.json();
console.log(data);

What Can You Build?

Note: These code examples are AI-generated and unverified. Always refer to the official API documentation for accurate usage.

Common Errors & Troubleshooting

Generated guidance based on this API's documentation, not observed by us. Treat it as a starting point and check against the provider's own error reference.

403 Forbidden The newer PurpleAir API v1 requires an API key passed as the X-API-Key header.
✓ Register at develop.purpleair.com to obtain a free API key and include it in every request header.
Empty or null sensor readings Some sensors go offline or report null values when they malfunction or lose connectivity.
✓ Filter out entries where pm2.5_atm is null before processing; add a freshness check using the last_seen timestamp.
Rate limit exceeded Polling too frequently against the API exceeds the allowed request rate.
✓ Cache sensor data locally and poll no more than once per minute per sensor to stay within rate limits.

Metadata Score Breakdown

Estimated from metadata — endpoint not independently tested

This score is estimated from observable metadata — HTTPS support, authentication model, declared CORS, and documentation reachability — because the API requires authentication or exposes no publicly testable endpoint. The five-signal breakdown is only shown for live-tested APIs.

Metadata estimate · endpoint not independently tested

How is this scored? →

Technical Specifications

Auth No Auth
HTTPS REQUIRED
CORS UNKNOWN
Category Science & Math
Difficulty Beginner
Listing details not endpoint-verified

Related Tags

#science-and-math

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