Comprehensive guide to SI base units, derived units, and imperial conversions
| Physical Quantity | SI Unit | Symbol |
|---|---|---|
| Length | Meter | m |
| Mass | Kilogram | kg |
| Time | Second | s |
| Electric Current | Ampere | A |
| Temperature | Kelvin | K |
| Amount of Substance | Mole | mol |
| Luminous Intensity | Candela | cd |
| Quantity | Unit Name | Symbol | In SI Base Units |
|---|---|---|---|
| Area | Square meter | m² | m² |
| Volume | Cubic meter | m³ | m³ |
| Speed, Velocity | Meter per second | m/s | m·s⁻¹ |
| Acceleration | Meter per second² | m/s² | m·s⁻² |
| Frequency | Hertz | Hz | s⁻¹ |
| Force | Newton | N | kg·m·s⁻² |
| Pressure | Pascal | Pa | kg·m⁻¹·s⁻² |
| Energy, Work | Joule | J | kg·m²·s⁻² |
| Power | Watt | W | kg·m²·s⁻³ |
| Electric Charge | Coulomb | C | A·s |
| Electric Potential | Volt | V | kg·m²·s⁻³·A⁻¹ |
| Resistance | Ohm | Ω | kg·m²·s⁻³·A⁻² |
| Capacitance | Farad | F | kg⁻¹·m⁻²·s⁴·A² |
| Magnetic Flux | Weber | Wb | kg·m²·s⁻²·A⁻¹ |
| Magnetic Field | Tesla | T | kg·s⁻²·A⁻¹ |
| Inductance | Henry | H | kg·m²·s⁻²·A⁻² |
| Temperature Difference | Celsius | °C | K |
| Luminous Flux | Lumen | lm | cd·sr |
| Illuminance | Lux | lx | lm·m⁻² |
| Unit | Conversion |
|---|---|
| 1 kilometer (km) | = 0.6214 miles |
| 1 meter (m) | = 3.2808 feet |
| 1 centimeter (cm) | = 0.3937 inches |
| 1 millimeter (mm) | = 0.03937 inches |
| 1 mile | = 1.6093 km |
| 1 yard | = 0.9144 m |
| 1 foot | = 0.3048 m |
| 1 inch | = 2.54 cm |
| 1 nautical mile | = 1.852 km |
| 1 light year | = 9.461 × 10¹² km |
| Unit | Conversion |
|---|---|
| 1 metric ton (t) | = 1000 kg |
| 1 kilogram (kg) | = 2.2046 pounds |
| 1 gram (g) | = 0.03527 ounces |
| 1 milligram (mg) | = 0.001 g |
| 1 pound (lb) | = 0.4536 kg |
| 1 ounce (oz) | = 28.3495 g |
| 1 stone | = 6.3503 kg |
| 1 US ton | = 907.1847 kg |
| 1 atomic mass unit (u) | = 1.6605 × 10⁻²⁷ kg |
| Unit | Conversion |
|---|---|
| 1 cubic meter (m³) | = 1000 L |
| 1 liter (L) | = 0.2642 gallons |
| 1 milliliter (mL) | = 1 cm³ |
| 1 gallon (US) | = 3.7854 L |
| 1 quart (US) | = 0.9464 L |
| 1 pint (US) | = 0.4732 L |
| 1 cup | = 236.588 mL |
| 1 fluid ounce | = 29.5735 mL |
| 1 tablespoon | = 14.7868 mL |
| 1 teaspoon | = 4.9289 mL |
| Unit | Conversion |
|---|---|
| 1 square km (km²) | = 0.3861 sq miles |
| 1 hectare (ha) | = 2.4711 acres |
| 1 square meter (m²) | = 10.7639 sq ft |
| 1 square cm (cm²) | = 0.1550 sq in |
| 1 acre | = 4046.86 m² |
| 1 square mile | = 2.590 km² |
| 1 square foot | = 0.0929 m² |
| 1 square inch | = 6.4516 cm² |
| From | To | Formula |
|---|---|---|
| Celsius (°C) | Fahrenheit (°F) | °F = (°C × 9/5) + 32 |
| Fahrenheit (°F) | Celsius (°C) | °C = (°F - 32) × 5/9 |
| Celsius (°C) | Kelvin (K) | K = °C + 273.15 |
| Kelvin (K) | Celsius (°C) | °C = K - 273.15 |
| Fahrenheit (°F) | Kelvin (K) | K = (°F - 32) × 5/9 + 273.15 |
| Freezing point | 0°C = 32°F = 273.15 K | |
| Boiling point | 100°C = 212°F = 373.15 K | |
| Absolute zero | -273.15°C = -459.67°F = 0 K | |
| Conversion | Formula |
|---|---|
| m/s to km/h | × 3.6 |
| km/h to m/s | × 5/18 |
| m/s to mph | × 2.23694 |
| mph to m/s | × 0.44704 |
| km/h to mph | × 0.621371 |
| mph to km/h | × 1.60934 |
| 1 knot | = 1.852 km/h |
| 1 Joule (J) | = 0.239 cal |
| 1 calorie (cal) | = 4.184 J |
| 1 kWh | = 3.6 × 10⁶ J |
| 1 eV | = 1.602 × 10⁻¹⁹ J |
| Unit | Conversion |
|---|---|
| 1 Pascal (Pa) | = 1 N/m² |
| 1 kPa | = 1000 Pa |
| 1 bar | = 100 kPa = 10⁵ Pa |
| 1 atm | = 101.325 kPa = 760 mmHg |
| 1 psi | = 6.89476 kPa |
| 1 mmHg | = 133.322 Pa |
| 1 torr | = 133.322 Pa |
| Standard atmosphere: 1 atm = 14.696 psi | |
| Unit | Equivalent |
|---|---|
| 1 minute | = 60 seconds |
| 1 hour | = 60 minutes = 3600 seconds |
| 1 day | = 24 hours = 86,400 seconds |
| 1 week | = 7 days |
| 1 year (common) | = 365 days |
| 1 year (leap) | = 366 days |
| 1 decade | = 10 years |
| 1 century | = 100 years |
| 1 millennium | = 1000 years |