Best Science & Math APIs in 2026

The top 15 of 59 free Science & Math APIs, ranked by how easy they are to start with (API key, HTTPS, CORS), how reliable they are in our daily health checks, and what developers rate them. GBIF API takes the top spot.

Last tested Oct 24, 2026 · Rankings update daily

1
GBIF API
Online · 115 ms
Global Biodiversity Information Facility. A free science & math API by gbif.org.
- No API key needed
- Fast: 115 ms response
- Callable from the browser (CORS)
- HTTPS
No authHTTPSCORS
2
Macrostrat API
Online · 694 ms
Geologic maps, rock columns and stratigraphy data.
- No API key needed
- Returns JSON at its URL
- Callable from the browser (CORS)
- HTTPS
No authHTTPSCORS
3
Chempirical API
Online · 533 ms
Chemical compounds with physical data, reactions and substructure search.
- No API key needed
- Callable from the browser (CORS)
- HTTPS
No authHTTPSCORS
4
CycleCalcs API
Online · 714 ms
Interpreted astronomy: sun and moon times, moon phases, planets, eclipses, seasons.
- No API key needed
- Callable from the browser (CORS)
- HTTPS
No authHTTPSCORS
5
Europe PMC API
Online · 118 ms
Life-science literature search with abstracts, citations and full-text links.
- No API key needed
- Fast: 118 ms response
- Callable from the browser (CORS)
- HTTPS
No authHTTPSCORS
6
iNaturalist API
Online · 1121 ms
Citizen-science wildlife observations with species identification and mapping.
- No API key needed
- Callable from the browser (CORS)
- HTTPS
No authHTTPSCORS
7
Launch Library 2 API
Online · 876 ms
Spaceflight launches and events database.
- No API key needed
- Callable from the browser (CORS)
- HTTPS
No authHTTPSCORS
8
MathJS API
Online · 934 ms
Evaluate math expressions via GET or POST as JSON.
- No API key needed
- Callable from the browser (CORS)
- HTTPS
No authHTTPSCORS
9
Oliver's mTOR Atlas API
Online · 739 ms
Curated mTOR research: studies by evidence type, pathway claims, open questions.
- No API key needed
- Callable from the browser (CORS)
- HTTPS
No authHTTPSCORS
10
OpenAlex API
Online · 864 ms
Open catalog of scholarly works, authors, institutions, sources, and concepts.
- No API key needed
- Callable from the browser (CORS)
- HTTPS
No authHTTPSCORS
11
Remote Calc API
Online · 661 ms
Decodes base64 encoding and parses it to return a solution to the calculation in JSON.
- No API key needed
- Callable from the browser (CORS)
- HTTPS
No authHTTPSCORS
12
Tallytopia API
Online · 420 ms
Calculators for finance, health, math, space and sports with step-by-step results.
- No API key needed
- Callable from the browser (CORS)
- HTTPS
No authHTTPSCORS
13
Unpaywall API
Online · 654 ms
Open-access status and legal full-text links for scholarly articles.
- No API key needed
- Callable from the browser (CORS)
- HTTPS
No authHTTPSCORS
14
ENA API
Online · 564 ms
Nucleotide sequences, genomes and raw reads archive.
- No API key needed
- Callable from the browser (CORS)
- HTTPS
No authHTTPSCORS
15
MyGene.info API
Online · 1048 ms
Gene annotation queries and ID lookup.
- No API key needed
- Callable from the browser (CORS)
- HTTPS
No authHTTPSCORS

Science & Math APIs compared

Top Science & Math APIs compared
API	API key	HTTPS	CORS	Uptime	Response	Rating
GBIF	No	Yes	Yes	Up	115 ms	Not rated
Macrostrat	No	Yes	Yes	Up	694 ms	Not rated
Chempirical	No	Yes	Yes	Up	533 ms	Not rated
CycleCalcs	No	Yes	Yes	Up	714 ms	Not rated
Europe PMC	No	Yes	Yes	Up	118 ms	Not rated
iNaturalist	No	Yes	Yes	Up	1121 ms	Not rated
Launch Library 2	No	Yes	Yes	Up	876 ms	Not rated
MathJS	No	Yes	Yes	Up	934 ms	Not rated
Oliver's mTOR Atlas	No	Yes	Yes	Up	739 ms	Not rated
OpenAlex	No	Yes	Yes	Up	864 ms	Not rated

More Science & Math APIs

Best Science & Math API FAQ

What is the best free Science & Math API in 2026?

Based on access, reliability and developer ratings, the top free Science & Math APIs right now are GBIF API, Macrostrat API and Chempirical API. GBIF API ranks first. Rankings update daily from health checks of all 59 Science & Math APIs in the directory.

What is the best Science & Math API without an API key?

GBIF API, Macrostrat API and Chempirical API need no API key, so you can call them without signing up. 51 of the 59 ranked Science & Math APIs are keyless.

Which Science & Math API works from the browser?

GBIF API, Macrostrat API and Chempirical API support CORS over HTTPS, so front-end JavaScript can call them directly without a proxy.

How are these APIs ranked?

Each API gets a score from: no API key (+), HTTPS (+), CORS support (+), 30-day uptime and response time from our daily health checks, and ratings from developers on this site. APIs that failed three checks in a row are left out until they recover.