Unit Convert API - Free Length Weight Temp
Convert a numeric value from one unit to another. Supports length (m, ft, in, km, mi), weight (kg, lb, oz, g), temperature (C, F, K), volume (L, gal, mL), speed (m/s, km/h, mph), and more.
Code examples
curl -X POST https://api.botoi.com/v1/units/convert \
-H "Content-Type: application/json" \
-d '{"value":100,"from":"km","to":"mi"}'When to use this API
E-commerce product dimensions
Convert product dimensions between metric and imperial units based on the customer shipping region.
Fitness and health apps
Convert between kg and lb, km and mi, or Celsius and Fahrenheit based on user locale preferences.
Scientific data processing
Normalize measurements from different lab instruments (mL to L, mg to g) into consistent units before analysis.
Frequently asked questions
Which unit categories are supported?
Length, weight/mass, temperature, volume, speed, area, time, and data storage (bytes, KB, MB, GB, TB).
Can I convert between incompatible units?
No. Converting between different categories (e.g., kg to meters) returns an error. Both units must belong to the same category.
How precise are the conversions?
Results are accurate to at least 6 significant digits. Temperature conversions use exact formulas.
Are unit abbreviations case-sensitive?
Unit names are case-insensitive. "KM", "km", and "Km" all work for kilometers.
Can I get the conversion formula?
Yes. The response includes a formula field showing the conversion factor (e.g., "1 km = 0.621371 mi").
Get your API key
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