A deterministic Indian income-tax API — Old vs New regime, multi-year, fully explainable. The public endpoint is free with no signup; paid tiers add higher quotas and are billed and metered through RapidAPI.
Prices are launch hypotheses (USD) and will be corrected by real usage — see the pricing rationale in our docs. RapidAPI handles billing and metering.
$0
500 requests / month
60 req/min
$10 /mo
10,000 requests / month
60 req/min
$29 /mo
100,000 requests / month
120 req/min
$99 /mo
1,000,000 requests / month
300 req/min
Payroll platforms, fintechs, enterprises. Negotiated volume + SLA · Direct API keys (off-marketplace) · Dedicated support + custom regimes · Self-host / on-prem option · Invoicing (not card).
The market has full-compliance suites and calculators, but a lightweight, deterministic, well-documented tax-calculation API is an underserved gap.
| Capability | Esytol API | Sandbox by Quicko | ClearTax |
|---|---|---|---|
| Focus | Tax calculation API | Compliance/filing platform | Filing + compliance suite |
| Old vs New regime + §-level trace | Yes | — | — |
| Self-serve on RapidAPI | Yes | — | — |
| Public free tier, no signup | Yes | — | — |
| Deterministic (identical in = identical out) | Yes | — | — |
Comparison of capabilities only. Competitor names are cited from our internal research; competitor traffic, pricing, and market-share figures are not asserted here (unverified — never invented).