Percentage Calculator API — Free & Private

A free edge API by formatho.com, privacy-first tools.

Open the full browser tool →

Free, no signup, runs entirely in your browser — your data never leaves your device.

🔓 Free🔒 Zero tracking🚫 No data collection⚡ Edge-fast

Usage

# What is 15% of 200?
curl "https://percentage-calculator-formatho.filesformatho.workers.dev/api?x=15&y=200"

# 30 is what percent of 200?
curl "https://percentage-calculator-formatho.filesformatho.workers.dev/api?x=30&y=200&action=isWhatPercent"

# Percentage change from 150 to 180
curl "https://percentage-calculator-formatho.filesformatho.workers.dev/api?from=150&to=180"

Three actions in one endpoint: percentOf (X% of Y), isWhatPercent (X is what % of Y) and percentChange (percentage increase/decrease from → to). Without action, both X/Y actions are computed together.

Full parameter reference: /api endpoint.

Privacy-first: numbers are computed in-memory at the edge and never logged or stored.

Full browser tool

Calculate percentages entirely client-side: Percentage Calculator on formatho.com.

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