Length
| Conversion | Value |
|---|---|
| 1 cm | 10 mm |
| 1 m | 100 cm |
| 1 km | 1000 m |
| 1 inch | 2.54 cm |
| 1 foot | 12 inches = 30.48 cm |
| 1 yard | 3 feet = 0.9144 m |
| 1 mile | about 1.609 km |
Mass (weight)
| Conversion | Value |
|---|---|
| 1 g | 1000 mg |
| 1 kg | 1000 g |
| 1 quintal | 100 kg |
| 1 tonne | 1000 kg = 10 quintals |
| 1 pound | about 453.6 g |
Capacity and volume
| Conversion | Value |
|---|---|
| 1 L | 1000 mL |
| 1 kL | 1000 L |
| 1 mL | 1 cm3 |
| 1 L | 1000 cm3 |
| 1 m3 | 1000 L = 1,000,000 cm3 |
Time
| Conversion | Value |
|---|---|
| 1 minute | 60 seconds |
| 1 hour | 60 minutes = 3600 seconds |
| 1 day | 24 hours |
| 1 week | 7 days |
| 1 year | 12 months = 365 days (366 in a leap year) |
| 1 decade | 10 years |
| 1 century | 100 years |
Area
| Conversion | Value |
|---|---|
| 1 m2 | 10,000 cm2 |
| 1 hectare | 10,000 m2 |
| 1 km2 | 100 hectares = 1,000,000 m2 |
| 1 acre | about 4,047 m2 (0.4047 hectare) |
Temperature, speed and money
| Idea | Rule |
|---|---|
| Celsius to Fahrenheit | °F = (°C × 9/5) + 32 |
| Fahrenheit to Celsius | °C = (°F - 32) × 5/9 |
| Celsius to Kelvin | K = °C + 273 (273.15 for exact work) |
| Water freezes and boils | 0 °C (32 °F) and 100 °C (212 °F) |
| km per hour to metres per second | Multiply by 5/18 |
| Metres per second to km per hour | Multiply by 18/5 (or 3.6) |
| Money | 100 paise = 1 rupee |
Indian and international number names
| Name | Number |
|---|---|
| 1 thousand | 1,000 |
| 1 lakh | 1,00,000 (105) |
| 10 lakh = 1 million | 10,00,000 |
| 1 crore | 1,00,00,000 (107) = 100 lakh |
| 100 crore = 1 billion | 1,00,00,00,000 (109) |
Computer storage
| Unit | Size |
|---|---|
| 1 byte | 8 bits |
| 1 KB (kilobyte) | 1024 bytes |
| 1 MB (megabyte) | 1024 KB |
| 1 GB (gigabyte) | 1024 MB |
| 1 TB (terabyte) | 1024 GB |
SI units of common quantities
| Quantity | SI unit | Symbol |
|---|---|---|
| Length | metre | m |
| Mass | kilogram | kg |
| Time | second | s |
| Temperature | kelvin | K |
| Electric current | ampere | A |
| Force | newton | N |
| Work and energy | joule | J |
| Power | watt (1 W = 1 J/s) | W |
| Pressure | pascal | Pa |
| Frequency | hertz | Hz |
| Electric charge | coulomb | C |
| Potential difference | volt | V |
| Resistance | ohm | Ω |