How to Convert Units Online Without Memorizing Formulas

To convert a unit, open the Unit Converter, pick a category — Length, Weight, Temperature, Volume, Data, Time or Speed — type a value, and choose the unit you're starting from. Every other unit in that category updates instantly, so you see the full conversion at once instead of running one formula at a time.

What the Unit Converter does

Most converters make you pick a "from" unit and a "to" unit and hand back one number. The Unit Converter skips that step: once you've typed a value and picked a starting unit, it lists every unit in the category side by side — so converting 1 meter to feet also shows you inches, yards and miles in the same glance, with no extra clicks. That's useful when you're not sure which unit you actually need, or when you want to sanity-check a conversion against a couple of others at once.

How to convert units with Toolbench

1. Open the Unit Converter.
2. Pick a category from the row of pills at the top: Length, Weight, Temperature, Volume, Data, Time or Speed.
3. Type a number into the Value field.
4. Use the dropdown next to it to choose the unit that value is in.
5. Read the result in the Equals · click to copy panel on the right — it lists every unit in the category, with your starting unit highlighted.
6. Click any row to copy that converted value.

If the Value field doesn't contain a valid number, the tool shows "Enter a number." instead of a result. Commas are fine — typing 1,000 works the same as 1000.

Example: converting 1 meter

The tool opens on the Length category with a value of 1 and Meters selected. Here's exactly what that produces:

Unit	1 meter equals
Millimeters	1000
Centimeters	100
Meters	1
Kilometers	0.001
Inches	39.37007874
Feet	3.280839895
Yards	1.093613298
Miles	0.0006213711922

Change the Value field to anything else — say, 5 — and every row recalculates against the new number without touching the unit dropdown.

Example: temperature doesn't scale the same way

Length, weight, volume, data, time and speed are all straight multiplication (double the meters, double the feet). Temperature isn't — Celsius, Fahrenheit and Kelvin need an offset, not just a ratio. Converting 100°F: it's 37.77777778°C and 310.9277778 K, not a simple multiple of the Fahrenheit value.

Reference: categories and units

Category	Units available
Length	mm, cm, m, km, in, ft, yd, mi
Weight	mg, g, kg, metric tons, oz, lb, stone
Temperature	°C, °F, K
Volume	mL, L, m³, tsp, tbsp, fl oz, cup, pt, qt, gal (US)
Data	bit, B, KB, MB, GB, TB, KiB, MiB, GiB
Time	ms, s, min, h, d, week, month (avg), year (avg)
Speed	m/s, km/h, mph, knots, ft/s

Tips and common mistakes

• KB and KiB aren't the same number. The Data category keeps decimal units (KB, MB, GB, TB — powers of 1,000) separate from binary units (KiB, MiB, GiB — powers of 1,024). 1 GB is 1,000,000,000 bytes but only about 0.931 GiB — mixing them up is one of the most common unit mistakes.
• Volume and weight here use US measures. Teaspoons, tablespoons, cups, pints, quarts, gallons, ounces and pounds are all US customary units, not UK/imperial, which use different volumes for some of these.
• "Months" and "years" in the Time category are averages, not calendar-exact — a month is treated as roughly 30.44 days to account for varying month lengths.
• Switching categories resets the unit, not the value — your number carries over, so switching from Length to Weight mid-task won't lose what you typed.
• The highlighted row is your starting unit — useful for confirming at a glance which unit you converted from before you read the rest of the list.

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Frequently asked questions

Does the Unit Converter handle temperature differently from other units?

Yes. Celsius, Fahrenheit and Kelvin need an offset as well as a scale factor, so the tool uses the standard conversion formulas for temperature instead of the straight multiplication it uses for length, weight, volume, data, time and speed.

What's the difference between GB and GiB in the Data category?

GB (gigabyte) is a decimal unit equal to 1,000,000,000 bytes. GiB (gibibyte) is a binary unit equal to 1,073,741,824 bytes. The Data category lists both so you can convert to whichever one your use case actually needs.

Is my data sent to a server when I convert units?

No. Conversions happen in your browser as you type. If you're signed in, your value and unit selections sync privately to your account; if you're signed out, nothing is saved anywhere.

Can I convert more than one unit at a time?

The tool converts one value across every unit in a category at once — so converting 1 meter shows you millimeters through miles in a single view, rather than making you repeat the conversion unit by unit.

Why does the tool show "Enter a number"?

That message appears when the Value field doesn't contain something the tool can parse as a number. Clear the field and type a plain number (commas are allowed) to get a result again.