A quick reference for converting between metric and imperial units: length, mass, volume and temperature, plus the fractional-inch to millimeter table people reach for when working with tools and hardware. Values are rounded for everyday use.
📄 Download the printable unit conversion chart (PDF)
A one-page printable conversion chart for metric and imperial units. → Download the unit conversion chart (PDF)
Length
| Unit | Equals |
|---|---|
1 inch (in) |
25.4 mm / 2.54 cm |
1 foot (ft) |
30.48 cm / 0.305 m |
1 yard (yd) |
0.914 m |
1 mile (mi) |
1.609 km |
1 centimeter (cm) |
0.394 in |
1 meter (m) |
3.281 ft / 1.094 yd |
1 kilometer (km) |
0.621 mi |
Mass / weight
| Unit | Equals |
|---|---|
1 ounce (oz) |
28.35 g |
1 pound (lb) |
453.6 g / 0.454 kg |
1 stone (st) |
6.35 kg / 14 lb |
1 gram (g) |
0.035 oz |
1 kilogram (kg) |
2.205 lb |
1 tonne (t) |
1000 kg / 2205 lb |
Volume
| Unit | Equals |
|---|---|
1 teaspoon (tsp) |
5 ml |
1 tablespoon (tbsp) |
15 ml |
1 fluid ounce (fl oz) |
29.6 ml |
1 cup (US) |
237 ml |
1 pint (US) |
473 ml |
1 quart (US) |
946 ml |
1 gallon (US) |
3.785 L |
1 liter (L) |
33.8 fl oz / 4.23 cups |
Temperature (common points)
| Celsius | Fahrenheit |
|---|---|
-40 C |
-40 F |
0 C |
32 F |
20 C |
68 F |
37 C |
98.6 F |
100 C |
212 F |
180 C |
356 F |
Fractional inch to mm
| Inch | Millimeters |
|---|---|
1/16 in |
1.6 mm |
1/8 in |
3.2 mm |
3/16 in |
4.8 mm |
1/4 in |
6.4 mm |
3/8 in |
9.5 mm |
1/2 in |
12.7 mm |
5/8 in |
15.9 mm |
3/4 in |
19.1 mm |
7/8 in |
22.2 mm |
1 in |
25.4 mm |
Temperature formulas
- Fahrenheit to Celsius: (F minus 32) times 5/9
- Celsius to Fahrenheit: (C times 9/5) plus 32
- Celsius to Kelvin: C plus 273.15
So 20 C is (20 times 9/5) plus 32, which is 68 F.
Frequently asked questions
How many mm are in an inch? Exactly 25.4 mm. So 1/2 inch is 12.7 mm and 1/4 inch is 6.35 mm. To go the other way, divide millimeters by 25.4.
How do I convert Celsius to Fahrenheit? Multiply the Celsius value by 9/5 (that is 1.8) and add 32. For example, 20 C is 20 times 1.8 plus 32, which equals 68 F.
How many grams are in a pound? One pound is about 453.6 grams, or 0.454 kilograms. One kilogram is about 2.205 pounds.
How many milliliters are in a cup? A US cup is about 237 ml. A tablespoon is 15 ml and a teaspoon is 5 ml, so a cup is roughly 16 tablespoons.