Unit Converter
Convert between units of length, weight, temperature, area, volume, speed, time, and digital storage. Two-way and live — every keystroke updates the result and a full conversion table, right in your browser.
1 metre = 0.001 kilometre
1 metre in every Length unit
All conversions run entirely in your browser — nothing you type is uploaded or stored.
Understanding the Unit Converter
The Unit Converter turns a value from one unit into another across eight everyday categories: Length, Weight/Mass, Temperature, Area, Volume, Speed, Time, and Digital Storage. It is built for students, engineers, cooks, travelers, and developers who need a fast, dependable answer without installing anything or signing up. Pick a category, type a number, choose your from and to units, and the result appears instantly — alongside a complete table showing your value in every unit of that category. A swap button flips the direction, quick-convert presets jump to common pairs in one click, and copy buttons grab any result. You can also download the full conversion table as a CSV. Everything is computed in your browser, so nothing you type is ever uploaded or stored.
How it works
Every category except Temperature is defined by storing each unit's size relative to a base unit (metre, gram, litre, byte, and so on). To convert, the tool multiplies your value by the source unit's factor to reach the base, then divides by the target unit's factor: result = value × fromFactor ÷ toFactor. Temperature is handled separately because it is not a simple ratio — Celsius, Fahrenheit, and Kelvin each convert to and from a Celsius base using exact formulas. Results are formatted to about six significant figures with trailing zeros trimmed, so you get clean numbers instead of floating-point noise.
Worked example
Length example: select Length, enter 5, set from = mile and to = kilometre. The tool multiplies 5 by the mile factor (1609.344 metres) to get 8046.72 metres, then divides by the kilometre factor (1000) to give 8.04672 km. The table below simultaneously shows that same 5 miles as 8046.72 m, 804672 cm, 8800 yards, 26400 feet, and 4.34488 nautical miles — each with its own copy button. Temperature example: select Temperature, enter 32, set from = Fahrenheit and to = Celsius. Because temperature is not a ratio, the tool applies the exact formula °C = (°F − 32) × 5/9, so 32°F becomes exactly 0°C — the freezing point of water. Enter 98.6°F and you get 37°C (normal body temperature); enter −40 and both scales read −40, the one point where they meet. This formula-based handling is why temperature is treated differently from the simple multiply-and-divide used for length, weight, and the other categories.
Tips & common mistakes
- Use the quick-convert presets (mi↔km, °C↔°F, lb↔kg, in→cm, L→gal) to jump straight to a common conversion without picking the category and both units by hand.
- Digital Storage uses binary (1024-based) multiples here, so 1 KB = 1024 bytes — this matches how operating systems report sizes, not the decimal 1000-based definition drive makers print on the box.
- Temperature uses real formulas, not a ratio, so negative values work correctly: -40 °C equals exactly -40 °F.
- Time units are approximate by design — month is fixed at 30 days and year at 365 days, so they ignore leap years and calendar variation.
- US volume units (gallon, quart, pint, cup, fluid ounce) differ from UK/imperial measures; this tool uses the US definitions.
- Use the swap button to reverse direction instantly instead of re-selecting both units, or Download CSV to save the whole conversion table for your records.
- Results show about six significant figures; for extreme magnitudes the tool switches to scientific notation to stay accurate.
Related tools
Frequently Asked Questions
Which categories of units can it convert?
Eight: Length, Weight/Mass, Temperature, Area, Volume, Speed, Time, and Digital Storage. Pick a category at the top, choose your from and to units, and the result updates instantly along with a full table of every unit in that category.
Does it handle temperature correctly?
Yes. Temperature is not a simple ratio, so Celsius, Fahrenheit, and Kelvin use exact formulas — for example F = C × 9/5 + 32 and K = C + 273.15 — rather than a single multiplier. This gives correct results, including negative temperatures.
Are the digital storage units binary?
Yes. This tool uses binary (1024-based) multiples, so 1 KB = 1024 bytes, 1 MB = 1024 KB, and so on up to PB. That matches how operating systems usually report file and disk sizes.