Mass Unit Converter
Effortlessly switch between any mass units. Our tool provides instant and accurate conversions for your needs.
Fast, Free, Private Mass Unit Converter (Offline)
Convert mass units instantly kg, lb, g, oz, t, st, US ton, imperial ton, mg, and µg. 100% client side, lifetime free, unlimited use. Top, fast, best in class. Your information is 100% confidential and secure.
No uploads, no sign ups, truly private. Works great online and offline after first load.
Why people love this mass converter
Offline & secure
Runs entirely in your browser. Your values never leave your device.
Unlimited & free forever
No accounts, no limits convert as much as you want.
Fast & simple
Pick units, type a value, get results instantly with clear precision.
Works everywhere
Modern browsers on Windows, Mac, Linux, and mobile devices.
No data collected
100% client-side processing keeps your data private.
Accurate results
Reliable conversion factors with smart rounding for readability.
Popular uses worldwide
Cooking & baking
Convert g/oz and kg/lb for recipes and meal prep.
Fitness & nutrition
Check body weight in kg, lb, or st. Track macros by g/oz.
Shipping & logistics
Convert parcel and freight weights between kg, lb, and tons.
Science & lab
Use mg, µg, and g for experiments with consistent precision.
Manufacturing
Standardize BOMs and inventory across metric and imperial units.
Travel & aviation
Check baggage and cargo weights in local units.
How to convert mass units
- Select your “From” unit (e.g., pounds).
- Enter a value (e.g., 150).
- Select your “To” unit (e.g., kilograms).
- See instant results and the 1 unit summary below.
- Use “Reset” to start again.
Tip: Edit either side both fields update intelligently.
Supported units
Best practices
- Confirm the unit system (metric vs imperial) before sharing measurements.
- Use appropriate precision (e.g., g for recipes, mg/µg for lab work).
- Round only at the end if you’ll do further calculations.
- Keep original values for auditing and records.
Frequently Asked Questions
Is it private and secure?
Yes. Everything runs locally in your browser no uploads, no tracking, no servers.
Is it really free and unlimited?
Yes. Lifetime free, unlimited conversions, and no sign ups.
Which units are supported?
t, kg, g, mg, µg, imperial ton (long), US ton (short), st, lb, oz.
Does it work offline?
Yes. Your browser can cache assets after the first visit and run offline.
How accurate are results?
We use precise constants (e.g., 1 lb = 0.453592 kg) with smart rounding for readability.
US vs imperial tons?
US (short) ton = 907.185 kg. Imperial (long) ton = 1,016.05 kg.
Global availability (GEO)
Built for users worldwide: USA, UK, Canada, Australia, India, EU (Germany, France, Spain, Italy, Netherlands), Middle East (UAE, Saudi Arabia), Asia (Singapore, Malaysia, Philippines, Indonesia, Japan, South Korea), Africa (Nigeria, South Africa, Egypt), and Latin America (Brazil, Mexico, Argentina).
Also searched as: Mass unit converter, weight converter, kg to lb, lb to kg, grams to ounces, ounces to grams, tonnes to tons, stone to kg, kg to stone, imperial ton to metric tonne, US ton to metric ton, mg to g, microgram to milligram.
Multilingual: conversor de masa / convertir kg a libras (ES), convertisseur de masse / kg en lb (FR), Masseinheiten umrechnen / kg in Pfund (DE), convertitore di massa / kg in libbre (IT), conversor de massa / kg para lb (PT), конвертер массы / кг в фунты (RU), 質量換算 / キログラムからポンド (JA), 质量换算 / 千克转磅 (ZH), 질량 변환기 / kg를 lb로 (KO), kütle dönüştürücü / kg'den lb'ye (TR), konwerter masy / kg na funty (PL), massa omrekenen / kg naar lb (NL), bộ chuyển đổi khối lượng / kg sang lb (VI), konverter massa / kg ke lb (ID), ตัวแปลงหน่วยมวล / กก. เป็น ปอนด์ (TH), محول الكتلة / كيلوجرام إلى رطل (AR), द्रव्यमान कनवर्टर / किलोग्राम से पाउंड (HI).
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