Molicheck API alternatives

Anonymous JSON lab/GMP calculators (molarity, dilution, ICH limits); no API key. If it doesn't fit your project, here are the 10 best free Science & Math APIs to use instead in 2026, out of 59 in the directory.

For reference, Molicheck API: No API key needed · 100% uptime (30 days) · Callable from the browser (CORS).

1. 1

   Chempirical API

   Online · 1100 ms

   Chemical compounds with physical data, reactions and substructure search.

   • No API key needed
   • 100% uptime (30 days)
   • Callable from the browser (CORS)
   • HTTPS

   No authHTTPSCORS
2. 2

   CycleCalcs API

   Online · 1000 ms

   Interpreted astronomy: sun and moon times, moon phases, planets, eclipses, seasons.

   • No API key needed
   • 100% uptime (30 days)
   • Callable from the browser (CORS)
   • HTTPS

   No authHTTPSCORS
3. 3

   GBIF API

   Online · 1168 ms

   Global Biodiversity Information Facility. A free science & math API by gbif.org.

   • No API key needed
   • 100% uptime (30 days)
   • Callable from the browser (CORS)
   • HTTPS

   No authHTTPSCORS
4. 4

   Macrostrat API

   Online · 1499 ms

   Geologic maps, rock columns and stratigraphy data.

   • No API key needed
   • 100% uptime (30 days)
   • Returns JSON at its URL
   • Callable from the browser (CORS)

   No authHTTPSCORS
5. 5

   Botlero API

   Online · 704 ms

   Sourced, quoted specs for humanoid robots.

   • No API key needed
   • Returns JSON at its URL
   • Callable from the browser (CORS)
   • HTTPS

   No authHTTPSCORS
6. 6

   DataCite API

   Online · 1879 ms

   Search and retrieve DOI metadata for research datasets and publications.

   • No API key needed
   • 100% uptime (30 days)
   • Callable from the browser (CORS)
   • HTTPS

   No authHTTPSCORS
7. 7

   iNaturalist API

   Online · 1340 ms

   Citizen-science wildlife observations with species identification and mapping.

   • No API key needed
   • 100% uptime (30 days)
   • Callable from the browser (CORS)
   • HTTPS

   No authHTTPSCORS
8. 8

   Launch Library 2 API

   Online · 1658 ms

   Spaceflight launches and events database.

   • No API key needed
   • 100% uptime (30 days)
   • Callable from the browser (CORS)
   • HTTPS

   No authHTTPSCORS
9. 9

   MathJS API

   Online · 1632 ms

   Evaluate math expressions via GET or POST as JSON.

   • No API key needed
   • 100% uptime (30 days)
   • Callable from the browser (CORS)
   • HTTPS

   No authHTTPSCORS
10. 10

    Oliver's mTOR Atlas API

    Online · 1423 ms

    Curated mTOR research: studies by evidence type, pathway claims, open questions.

    • No API key needed
    • 100% uptime (30 days)
    • Callable from the browser (CORS)
    • HTTPS

    No authHTTPSCORS

Molicheck API vs alternatives

Molicheck API compared with its alternatives

API	API key	HTTPS	CORS	Uptime	Response	Rating
Molicheck	No	Yes	Yes	100%	781 ms	Not rated
Chempirical	No	Yes	Yes	100%	1100 ms	Not rated
CycleCalcs	No	Yes	Yes	100%	1000 ms	Not rated
GBIF	No	Yes	Yes	100%	1168 ms	Not rated
Macrostrat	No	Yes	Yes	100%	1499 ms	Not rated
Botlero	No	Yes	Yes	83.3%	704 ms	Not rated
DataCite	No	Yes	Yes	100%	1879 ms	Not rated
iNaturalist	No	Yes	Yes	100%	1340 ms	Not rated
Launch Library 2	No	Yes	Yes	100%	1658 ms	Not rated

See also: best Science & Math APIs · all Science & Math APIs