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CONVERTERS

Unit Converter

Convert between length, weight, volume, area, speed, and temperature units, with a quick-reference table showing every unit at once.

Tool statusRuns in your browser
Preview
prontouso://converters/units
MULTIPLE SCALESAUTO CONVERT
MEASURE TYPEChoose the quantity you want to convert.
FromLENGTH
input in m
ToRESULT
1 m = 100 cm
Quick equivalentsLENGTH
1,000mm
100cm
0.001km
39.37007874in
3.2808399ft
1.0936133yd
0.00062137mi
0.00053996nmi

How it works

  1. Enter your input

    Fill in the values, paste your text, or upload the file this tool works with.

  2. See results instantly

    Most tools update live as you type; a few use a single button. Either way, the result appears right on this page.

  3. Use your results

    Copy, download, or share what the tool produces — you're always in control of the output.

Privacy and processing — Runs locally in your browser. This tool does not upload your input.

What is Unit Converter?

The Unit Converter converts length, area, volume, mass, temperature, time, speed, and data between each other, plus turns pixels into physical measurements by density (PPI) and typography units (rem, em, pt, %) relative to a configurable base size — all in the browser.

UNDERSTAND THE TOOL

How to convert units, screen sizes, and typography

The tool has three tabs: Measures for the 8 common categories, Screen & Print for pixels and density, and Typography for rem/em relative to a base size.

The 8 measurement categories

  • Length: millimeters to nautical miles, including inches, feet, and yards.
  • Area: square millimeters to acres, including hectares.
  • Volume: milliliters to gallons, plus teaspoon, tablespoon, cup, and fluid ounce (US cooking units).
  • Mass: milligrams to tonnes, including ounces, pounds, and stone.
  • Temperature: Celsius, Fahrenheit, and Kelvin.
  • Time: milliseconds to years (assuming a 30-day month and a 365-day year).
  • Speed: m/s, km/h, mph, and knots.
  • Data: bytes to terabytes (base 1000) and kibibytes to gibibytes (base 1024), plus bit.

Screen & Print: pixels depend on a density

A pixel isn't a fixed physical measurement — turning it into centimeters, inches, or typographic points requires assuming how many pixels fit in an inch (PPI). The CSS reference is 96 px per inch; print usually uses 300 PPI or higher.

  • px, cm, mm, and in convert using the configured PPI (or the 72, 96, 150, and 300 presets).
  • pt (point) and pc (pica) are fixed: 72 pt = 1 inch and 6 pc = 1 inch, always, regardless of PPI.
Pixels to inches
inches = px / PPI

Typography: rem and em are relative

rem and em don't have a fixed pixel value — they depend on the configured base size (the browser default is 16px). Adjust the base field before converting to reflect your project's actual root font size.

Unlike the Screen & Print tab, here pt always assumes the CSS reference of 96 px per inch (96/72), not the PPI you set on the other tab — the two tabs are independent.

rem/em to pixels
px = value × baseSize
Pixels to points (CSS)
pt = px × 72 / 96

Temperature isn't proportional

Unlike the other categories, temperature doesn't use a simple multiplication factor because the scales don't share the same zero — the conversion goes through Celsius as an intermediate reference.

Fahrenheit to Celsius
C = (F − 32) × 5 / 9

The quick-equivalents table

Below the converter, every other unit in the same category shows the value already converted, so you can compare several units at once without repeating the conversion manually.

Conversion notes

Every conversion runs in your browser, without sending values to a server. Very large or tiny results show as scientific notation; the copyable field uses a decimal point, while surrounding text uses a comma where your language expects it.

Frequently Asked Questions

Why does 96 px equal 2.54 cm on the Screen & Print tab?

Because 96 is the default PPI assumed by CSS: 96 px ÷ 96 PPI = 1 inch, and 1 inch equals 2.54 cm by definition. Change the PPI to simulate a screen or print output with a different density.

Does the Screen & Print tab's PPI affect the pt conversion on the Typography tab?

No — they're independent. Screen & Print uses whatever PPI you set; Typography always assumes 96 px per inch to calculate pt, which is the fixed reference CSS itself uses.

Why does data storage have two unit families (KB and KiB)?

KB, MB, GB, and TB use base 1000 (the storage-manufacturer standard), while KiB, MiB, and GiB use base 1024 (the operating-system and memory standard). A '500 MB' file and a '500 MiB' file aren't the same size — the gap grows with scale.

How does time handle months and years, which have variable length?

The tool assumes a fixed 30-day month and a fixed 365-day year so it can convert with simple multiplication. For a specific calendar month or year, the result can be off by a day or two.

Why does temperature need its own formula?

Celsius, Fahrenheit, and Kelvin start at different zero points, so converting between them requires addition and multiplication together, not just a single scaling factor — unlike every other category in this tool.

Can I convert US cooking measurements?

Yes — the Volume category includes teaspoon, tablespoon, cup, and fluid ounce (fl oz) in US units, alongside milliliters, liters, and gallons.

Why do some results show scientific notation?

Very large values (above 1 trillion) or very tiny ones (below 0.000001) become hard to read with normal decimals, so the display switches to notation such as 1.0000e+12.

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