Calculator API
Every DevPros calculator is a JSON endpoint — no signup, no API key, CORS-enabled. Pick a tool, set inputs, run it.
1. Pick an endpoint
2. Inputs
3. Request
GET /api/calc/minus-10-fahrenheit-to-celsius?f=72
Self-describing catalog
GET /api/calc lists all endpoints with field ids, types, defaults and options — enough to build a UI from the schema alone.
Same engine as the site
Responses include the exact result rows on the tool page plus worked-steps derivations where available.
Fair use
Free for reasonable use, no key required. High volume or an SLA? Get in touch.
Need a private endpoint or custom calculator?
We build bespoke calculation APIs and embeddable tools for UK and North American businesses.
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