Toolalize API alternatives
Unit and live currency conversion with NIST SI factors, no key needed. 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, Toolalize API: No API key needed · 100% uptime (30 days) · Returns JSON at its URL.
- 1
Chempirical API
Online · 1100 msChemical 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
CycleCalcs API
Online · 1000 msInterpreted 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
Molicheck API
Online · 781 msAnonymous JSON lab/GMP calculators (molarity, dilution, ICH limits); no API key.
- No API key needed
- 100% uptime (30 days)
- Callable from the browser (CORS)
- HTTPS
No authHTTPSCORS - 4
GBIF API
Online · 1168 msGlobal 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 - 5

Macrostrat API
Online · 1499 msGeologic 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 - 6
Botlero API
Online · 704 msSourced, quoted specs for humanoid robots.
- No API key needed
- Returns JSON at its URL
- Callable from the browser (CORS)
- HTTPS
No authHTTPSCORS - 7

DataCite API
Online · 1879 msSearch 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 - 8
iNaturalist API
Online · 1340 msCitizen-science wildlife observations with species identification and mapping.
- No API key needed
- 100% uptime (30 days)
- Callable from the browser (CORS)
- HTTPS
No authHTTPSCORS - 9
Launch Library 2 API
Online · 1658 msSpaceflight launches and events database.
- No API key needed
- 100% uptime (30 days)
- Callable from the browser (CORS)
- HTTPS
No authHTTPSCORS - 10
MathJS API
Online · 1632 msEvaluate math expressions via GET or POST as JSON.
- No API key needed
- 100% uptime (30 days)
- Callable from the browser (CORS)
- HTTPS
No authHTTPSCORS
Toolalize API vs alternatives
| API | API key | HTTPS | CORS | Uptime | Response | Rating |
|---|---|---|---|---|---|---|
| No | Yes | Yes | 100% | 1704 ms | Not rated | |
| No | Yes | Yes | 100% | 1100 ms | Not rated | |
| No | Yes | Yes | 100% | 1000 ms | Not rated | |
| No | Yes | Yes | 100% | 781 ms | Not rated | |
| No | Yes | Yes | 100% | 1168 ms | Not rated | |
| No | Yes | Yes | 100% | 1499 ms | Not rated | |
| No | Yes | Yes | 83.3% | 704 ms | Not rated | |
| No | Yes | Yes | 100% | 1879 ms | Not rated | |
| No | Yes | Yes | 100% | 1340 ms | Not rated |
See also: best Science & Math APIs · all Science & Math APIs
Toolalize API alternatives FAQ
What is the best free alternative to the Toolalize API in 2026?
The top-ranked free alternatives to the Toolalize API are Chempirical API, CycleCalcs API and Molicheck API, all in the Science & Math category. Rankings combine access (API key, HTTPS, CORS), daily uptime checks and developer ratings.
How many Science & Math APIs are similar to the Toolalize API?
The directory lists 56 other free Science & Math APIs. This page compares the top ones side by side.