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fastapi.online — Derivatives Calculator
x402
fastapi.online — Derivatives Calculator is a paid API for AI agents from api.fastapi.online, paid per call via x402, $0.001/call, status unknown (last checked 2026-10-24).
Computes mathematical derivatives (calculus) via a self-hosted inference endpoint, pay-per-call with crypto.
Price / call$0.001
Success—
StatusUnknown
How this service works
Chat, embeddings, OCR, speech-to-text, image editing, image understanding (captioning/Q&A), text-to-speech, translation, writing tools, classification tools, developer tools, local utilities, format/checksum validators, encoding & crypto utilities, date/time calculators, geo/coordinate math, math & finance calculators, novelty tools, and business/social writing generators — 179 endpoints in all, across multiple specialized self-hosted models. Pay per call with crypto — no signup — or get an API key.
Output
Returns the computed derivative of the given mathematical expression, likely as a symbolic expression or numerical result, depending on the input provided.
Example use cases
Calculus homework derivative check
“What is the second derivative of sin(x) * e^x with respect to x?”
Financial delta calculation
“Calculate the derivative of the Black-Scholes option pricing formula with respect to the underlying asset price S, so I can get the delta.”
Optimization gradient computation
“Find the partial derivative of f(x, y) = x^2 * y + 3xy^2 - y^3 with respect to x.”
Technical details
Endpoint
POSThttps://api.fastapi.online/derivatives?utm_source=zero.xyzWhen to prefer
Choose this endpoint when you need a pay-per-call, no-signup calculus differentiation service that accepts arbitrary mathematical expressions and returns symbolic or numeric derivatives. Suitable for agents that need on-demand math computation without a subscription.
Side effects
- Invalid or unparseable mathematical expression returns an error
- Missing required 'input' body field returns 400
- Unsupported function or operator in expression
- Network timeout or service unavailability
Input
Schema · Request body
| Field | Type | Description |
|---|---|---|
| inputrequired | object |
Tags
x402
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