Unitly
中文Hub
Free • Private • Nothing Sent

Free Unit Converter

Convert length, mass, temperature, volume, area, speed, time, and digital data entirely in your browser. Live results as you type. Optional share links use the URL hash and never expire. Your numbers are never uploaded.

🔒 Runs in your browser · Never uploaded · Share uses URL # only · Works offline · Free, no sign-up

Stores category + units + value (max 24 chars) in the URL # only. Do not put secrets in share links.

Anyone with the link can read the numbers. Never share passwords or private data this way.

Formula

1 cm = 0.3937007874 in

Common values

1 cm0.3937007874 in
5 cm1.96850394 in
10 cm3.93700787 in
25 cm9.84251969 in
50 cm19.68503937 in
100 cm39.37007874 in

A unit converter that never uploads your numbers

Unitly converts length, mass, temperature, volume, area, speed, time, and digital data with SI-base factors (and affine °C/°F/K). Everything runs in your browser. Optional share links store only category, units, and a short value in the URL hash — so nothing hits ToolBookly servers and the link never expires.

Features

  • Eight categories with live convert as you type
  • Swap from↔to, copy result, clear
  • Formula line + common-values table for the current pair
  • Optional hash share — never uploaded, never expires

Why Unitly?

  • 100% client-side: numbers are never sent or stored
  • Share via # hash that never expires and never hits the server
  • Works offline after first load; instant live convert
  • Free, no sign-up, no ad-tracker query logging

How to convert units

1
Pick a category

Length, mass, temperature, volume, area, speed, time, or digital data.

2
Choose From and To

Select units, then type a value — the result updates live.

3
Swap or copy

Flip direction, copy the result, or clear and start over.

4
Optional share via #

Copy a hash link with category + units + value — never uploaded, never expires.

Frequently Asked Questions

Are my numbers uploaded?
No. Unitly converts entirely in your browser. Values never leave your device. Optional share links store only category, units, and a short value in the URL hash (#), which never reaches the server as a query string.
How do I convert cm to inches?
Open the Length tab, set From to Centimetre (cm) and To to Inch (in), then type a number. The result updates live. 2.54 cm equals 1 inch.
How do I convert kg to lbs?
Open Mass, choose Kilogram (kg) → Pound (lb). One kilogram is about 2.20462 pounds. Swap flips the direction instantly.
How do I convert Celsius to Fahrenheit?
Open Temperature, choose Celsius (°C) → Fahrenheit (°F). The formula shown is °F = °C × 9/5 + 32. Round-trips through Kelvin work the same way.
What does the share link store?
Only category, from/to units, and a capped numeric value in the hash. Do not put secrets or passwords in share links. Links never expire and never hit ToolBookly servers.
Is Unitly free?
Yes. Free, no sign-up, no limits. It is part of the ToolBookly suite of browser tools.

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