Convertisseur d’unités
Choisissez un type de mesure — débit Internet (Mbit/s), énergie, puissance, pression — et convertissez entre unités métriques et impériales.
Calculer
La formule
Convert the source value to the category’s base unit, then divide by the target unit’s factor. Each category (length, data rate, energy, pressure, …) uses its own SI base so units never mix across dimensions.
Exemple détaillé
- 100 cm → metres
- 100 × 0.01 m/cm = 1 m
- 1 m → feet: 1 ÷ 0.3048 ≈ 3.28084 ft
Résultat: 100 cm = 1 m ≈ 3.28084 ft
How unit conversion works
Each category converts through one base unit. Switching category resets the unit lists so you never mix metres with litres or Mbit/s with MB.
Length, area, volume, mass
Length factors are exact international definitions (1 in = 0.0254 m, 1 ft = 0.3048 m). Area uses square metres. Volume uses litres (1 m³ = 1000 L) with US customary liquid measures. Mass uses kilograms (1 lb = 0.45359237 kg).
Digital storage vs internet speed
Digital storage uses bytes (kB/MB SI decimal; KiB/MiB IEC binary). Internet / data rate uses bits per second — ISP plans quote Mbit/s, while download managers often show MB/s (bytes). 8 Mbit/s ≈ 1 MB/s.
Energy, power, pressure, force
Energy converts through joules (including Wh, kWh, kcal, BTU). Power through watts (including mechanical horsepower). Pressure through pascals (bar, atm, psi, mmHg). Force through newtons (lbf, kgf).
Angle, frequency, speed, time
Angles convert through radians. Frequency through hertz (rpm = revolutions per minute). Travel speed through metres per second. Time through seconds.
Related tools
Temperature needs an offset, not a pure factor — use the temperature converter. Cooking volumes with ingredient densities use the cooking converter. Shape area from length × width uses the area calculator.
Faits intéressants
Bits vs bytes on your connection
A “100 Mbps” plan is megabits per second. Divide by 8 for a rough megabyte-per-second download rate (~12.5 MB/s) before protocol overhead.
SI vs binary prefixes
Hard-drive makers usually advertise GB as 10⁹ bytes, while operating systems often report GiB as 2³⁰ bytes — that gap is why free space looks smaller than the box promised.
Exact vs survey feet
Since 1959 the international foot is exactly 0.3048 m. Older US survey definitions can differ by tiny amounts in GIS work.
US liquid gallon
This converter uses the US liquid gallon (exactly 3.785411784 L), not the imperial gallon used in the UK.
Dimensional check
Writing units through a calculation catches errors: you cannot add metres to seconds without a conversion factor that makes sense.
Questions fréquentes
Choisissez Débit Internet, puis Mbit/s → MB/s. 8 bits = 1 octet : 80 Mbit/s ≈ 10 Mo/s (hors overhead).
Choisissez Longueur, puis in → cm. Multipliez par 2,54 (exact). Exemple : 10 in × 2,54 = 25,4 cm.
MB = 1 000 000 octets (SI). MiB = 1 048 576 octets (1024², IEC). Catégorie Stockage numérique.
Oui — catégorie Volume. Mesures liquides US en plus de ml, L et m³.
Non. Celsius ↔ Fahrenheit ↔ Kelvin nécessite un décalage. Utilisez le convertisseur de température.
Références
- SI units Official U.S. metrology guidance for SI units.
- NIST SP 811 — Guide to the SI Conversion factors and proper unit notation.
- BIPM SI Brochure International definitions of the metre and related units.
- IEC 80000-13 — Binary prefixes KiB, MiB, GiB definitions (powers of 1024).