plugmyagent

PubChem PUG REST

Science Data No key

AuthenticationNo key
Rate limit5 requests per second and 400 requests per minute per IP address.

Documentation: pubchem.ncbi.nlm.nih.gov ยท Checked Sep 13, 2026

About

PubChem is the U.S. National Institutes of Health's huge chemical database, and its PUG REST API lets you query it with simple URLs. Look up any compound by name and get its structure, molecular formula, safety data, drug information, and test results. It is free, needs no key, and covers over 100 million chemical records.

Details

No key needed. You can call it right away.

Auth: No key

Rate limit: 5 requests per second and 400 requests per minute per IP address.

Verified: 2026-09-13

Best for: personal developer fun

Read the docs Back to catalog

Setup

  1. Paste the example URL into your browser to get aspirin's data instantly, no signup needed.
  2. Swap in any chemical name or identifier in the URL.
  3. Add /PNG at the end of some endpoints to get structure images instead of JSON.
  4. Keep requests under 5 per second to stay within the published limits.
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