Science & Math — entry 016 of 28
Newton
Newton is a keyless calculator API deployed as a Vercel serverless function: the operation (simplify, factor, derive, integrate, and more) and expression are both encoded directly in the URL path, and it answers with a small JSON object containing the result. It's a solo open-source project (aunyks/newton-api) rather than a commercial service, so there's no pricing tier or rate limit to opt into.
Newton is a single keyless GET endpoint shaped as `newton.vercel.app/api/v2/:operation/:expression` — the math operation (simplify, factor, derive, integrate, zeroes, and more) and a URL-encoded expression both live in the path, and the response is a small JSON object echoing the operation, expression, and result.
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<a href="https://greatapis.com/api/newton/"><img src="https://greatapis.com/badge/newton.svg" alt="Scored 74 on greatapis.com"></a>Auth quickstart
- No account or key required — call any operation as a plain GET; there's nothing to register or attach.
- The expression must be URL-encoded in the path, not passed as a query string — `^` becomes `%5E`, `+` becomes `%2B`, and a literal `/` (fraction division) must be percent-encoded as `%2F`. Confirmed live this run: `.../simplify/1%2F2` returns `"result":"1/2"`, while the unencoded `.../simplify/1/2` silently 404s (the host treats the second `/` as an extra path segment, not part of the expression).
Your key is stored only in this browser (localStorage) and sent directly to the API — never to greatapis.
Simplify an algebraic expression
GEThttps://newton.vercel.app/api/v2/simplify/2%5E2%2B2(2)
{"operation":"simplify","expression":"2^2+2(2)","result":"8"}Captured byte-for-byte from this run's live probe.
Developer reference
https://newton.vercel.app/api/v2Gotchas & limits
- An unknown operation doesn't 404 — `.../bogusop/2%2B2` returns HTTP 400 with a JSON body `{"error":"Unknown operation"}`, confirmed live this run. Check the status code, not just whether a body came back.
- A literal, unencoded `/` inside the expression breaks routing rather than erroring cleanly: `.../simplify/1/2` returns Vercel's generic Next.js 404 HTML page (not Newton's own JSON error shape), while the percent-encoded `.../simplify/1%2F2` succeeds with `"result":"1/2"` — confirmed live this run.
- There is no discoverable list-of-operations route: both the bare `/api/v2` root and an operation with no expression (`.../simplify` alone) return the same generic 404 page as a bogus path, confirmed live this run. The ~15 supported operations are documented only in the project's own README, not in a machine-readable endpoint.
- CORS is wide open — a live probe with `Origin: https://example.com` returns `Access-Control-Allow-Origin: *` unconditionally, confirmed this run, so the endpoint can be called directly from browser JS.