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Unit Converter

Convert length, weight, temperature, volume, and speed. 100% offline.

📐 How the Unit Converter Works

Unit conversion uses a two-step base-unit normalisation approach. Every unit in a category is defined as a ratio relative to one chosen base unit. This makes adding new units trivial and keeps errors minimal.

Converted = InputValue × (FromFactor / ToFactor) Example base: 1 metre 1 km = 1000 m → factor 1000 1 cm = 0.01 m → factor 0.01 1 inch = 0.0254 m → factor 0.0254
1
Each unit stores a single number: how many base units it equals. Length base = metre; Weight base = kilogram; Temp uses special formulas.
2
To convert A → B: multiply the input by A's factor, then divide by B's factor. This converts via the common base.
3
Temperature is special: Celsius↔Fahrenheit uses an offset formula (°F = °C × 9/5 + 32), not a simple ratio, so it's handled separately.
Example: Convert 5 miles to kilometres.
1 mile = 1609.344 m  |  1 km = 1000 m
Result = 5 × (1609.344 / 1000) = 8.047 km

All conversion factors are hard-coded in the browser — no API calls needed.

Read: Unit Converter Guide

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