Convert between hundreds of units — length, mass, volume, temperature, area, speed, time, digital data, and more with a single click. Input never leaves your device — everything runs locally in your browser.
Content reviewed October 2026 · About Toolzum
Convert between time units including seconds, minutes, hours, days, weeks, months, and years with precise decimal results. Input never leaves your device — everything runs locally in your browser.
Convert speeds between km/h, mph, m/s, and knots instantly. Translate a 100 mph speed for any audience — free, local, no signup.
Convert length and distance between km, miles, meters, yards, feet, and inches. Simple and intuitive. Input never leaves your device — everything runs locally in your browser.
Estimate password crack times from length, charset, and attacker speed — entropy made visceral. Show why 8-char passwords fall in hours — local math, free, no signup.
Analyzes your writing with real-time word count, character counts with and without spaces, sentence and paragraph counts, plus estimated reading time (200 wpm) and speaking time (150 wpm). Essential for writers, students, and SEO professionals tracking length and pacing.
Length (mm, cm, m, km, in, ft, yd, mi) with more unit families available. Enter any value and see the conversion to all supported units instantly.
1 meter = 3.28084 feet. All conversions use internationally standardized factors.
1 inch = 2.54 cm exactly. This is a defined international agreement, not an approximation.
A marathon is 42.195 km (26.2 miles). The exact distance was standardized by the IAAF in 1921.
Yes. All conversions run locally in your browser using JavaScript. No data is sent to any server.
Length Converter
Convert length and distance between km, miles, meters, yards, feet, and inches. Simple and intuitive. Input never leaves your device — everything runs locally in your browser.
Weight Converter
Convert weight between kg, g, lb, oz, and stone. Supports both metric and imperial systems. Input never leaves your device — everything runs locally in your browser.
Volume Converter
Convert volume between liters, mL, gallons, quarts, fl oz, and cups. Handy for cooking, science, and travel. Input never leaves your device — everything runs locally in your browser.