Length
| Unit |
Metric equivalent |
| 1 inch |
2.54 cm |
| 1 foot |
30.48 cm |
| 1 mile |
1.609 km |
| 1 metre |
3.281 feet |
Weight / mass
| Unit |
Metric equivalent |
| 1 ounce (oz) |
28.35 g |
| 1 pound (lb) |
453.6 g |
| 1 kg |
2.205 pounds |
Volume
| Unit |
Metric equivalent |
| 1 US gallon |
3.785 L |
| 1 US pint |
0.473 L |
| 1 US cup |
236.6 mL |
| 1 tablespoon |
15 mL |
| 1 teaspoon |
5 mL |
Temperature
°F → °C : (F - 32) × 5/9
°C → °F : (C × 9/5) + 32
| °C |
°F |
| 0 |
32 |
| 20 |
68 |
| 37 |
98.6 |
| 100 |
212 |
Quick mental estimate for °C → °F: double the Celsius figure and add 30 (accurate to within a few degrees, close enough for a rough guess).
Speed and pressure
| Unit |
Metric equivalent |
| 1 mile/h (mph) |
1.609 km/h |
| 1 knot |
1.852 km/h |
| 1 psi (pound/square inch) |
0.0689 bar |
| 1 atm |
1.013 bar |
Area
| Unit |
Metric equivalent |
| 1 square foot (sq ft) |
0.0929 m² |
| 1 acre |
4,047 m² (~0.4 hectare) |
| 1 are |
100 m² |
| 1 hectare |
10,000 m² |
Digital storage
1 byte = 8 bits
1 KB = 1000 bytes · 1 KiB (kibibyte) = 1024 bytes
1 MB = 1000 KB · 1 MiB = 1024 KiB
1 GB = 1000 MB · 1 GiB = 1024 MiB
The gap between KB/MB/GB (base 1000, SI standard) and KiB/MiB/GiB (base 1024, binary standard) explains why a "1 TB" hard drive often shows up as roughly 931 GiB in your file explorer — manufacturers use base 1000, operating systems use base 1024.
Thanks for the feedback!