Rights

Licence
US Government work — public domain
Commercial reuse
Yes
Redistribution
Yes
Derivative use
Yes
Attribution required
No
Restrictions
Applies to material authored by US federal agencies. Third-party material carried within a federal product may be separately protected.
Terms last checked
23 August 2026

Access and coverage

Publisher
National Center for Biotechnology Information
Website
https://pubchem.ncbi.nlm.nih.gov/
API
https://pubchem.ncbi.nlm.nih.gov/rest/pug
Geographic coverage
Not geographic
Update frequency
daily
Formats
json, csv, api
Bulk download
Available
Registration required
No
Rate limit
5 requests per second
Cost to Hydrionis
Free
Domains
chemistry, contaminant