Convertisseur de base numérique
Convertissez des nombres entre binaire, octal, décimal et hexadécimal.
About Number Base Converter
Computers represent numbers in different bases. Binary (base 2) is used internally by all hardware. Octal (base 8) appears in file permissions (chmod). Hexadecimal (base 16) is everywhere in memory addresses, colors, and encoding. Type in any field to convert automatically to all other bases.
FAQ
- Qu'est-ce que la conversion de base ?
- Tout nombre peut s'écrire dans n'importe quel système positionnel. Le décimal utilise les chiffres 0 à 9, le binaire 0 à 1, l'hexadécimal 0 à 9 et A à F.
- Puis-je saisir des lettres hexadécimales en minuscules ?
- Oui. L'outil accepte les chiffres hexadécimaux en majuscules et en minuscules.
- Pourquoi l'hexadécimal utilise-t-il les lettres A à F ?
- L'hexadécimal nécessite 16 symboles. Après avoir utilisé 0 à 9 (10 symboles), A=10, B=11, C=12, D=13, E=14, F=15.
- La conversion de nombres négatifs est-elle prise en charge ?
- Pas actuellement. L'outil gère uniquement les entiers non négatifs.
À PROPOS DE CET OUTIL
Enter a number in binary, octal, decimal, or hexadecimal and instantly see it converted into the other three bases, updating as you type. Under the hood this is just repeated division and remainder tracking, or grouping bits by powers of two, but doing it by hand is slow and error-prone for anything beyond small numbers. Programmers reach for base conversion when reading memory addresses, working with bitmasks and flags, translating color codes, or debugging low-level code where hex and binary representations matter. It's also a common aid in computer science courses for building intuition about how positional number systems relate to each other.
COMMENT UTILISER
- Type a number into any one of the four fields (binary, octal, decimal, hex).
- The other three fields update automatically with the converted value.
- Use only valid digits for each base - 0/1 for binary, 0-7 for octal, 0-9 for decimal, 0-9/A-F for hex.
- Clear a field and type a new number to start a fresh conversion.
- Copy the result you need directly from its field.
CAS D'USAGE COURANTS
- A student checking manual binary-to-decimal homework conversions.
- A developer translating a hex memory address from a debugger into decimal to compare against a log entry.
- Someone decoding a hex color code's decimal RGB components for a design tool.
- A network engineer converting a subnet-related value between decimal and binary.
- An embedded systems programmer reading register values expressed as octal or hex constants in a datasheet.
CONSEILS ET ERREURS COURANTES
- Hex letters A-F are case-insensitive here, though many codebases follow a lowercase convention for readability.
- This tool converts unsigned magnitudes only - for a negative value in a fixed-width register, apply two's complement encoding separately.
- Very large numbers can exceed the 32-bit or 64-bit ranges used in some programming languages, even though the converter itself has no such limit.
- Leading zeros are cosmetic - 0x0A and 0xA are the same hex value.
AUTRES QUESTIONS
- Why does the binary output look so much longer than the decimal input?
- Binary only has two digits per position, so it takes roughly 3.3 times as many digits as decimal to represent the same value - decimal 255 becomes 11111111 in binary.
- Does this tool support two's complement for negative binary numbers?
- No, it converts unsigned magnitudes only. To represent a negative number in a fixed bit width, such as an 8-bit or 32-bit signed integer, you need to apply two's complement encoding yourself.
- What's the difference between octal and hex for representing the same binary value?
- Octal groups binary digits in sets of 3 (2^3=8), while hex groups them in sets of 4 (2^4=16). Hex is more common in modern computing because it aligns cleanly with 8-bit bytes and 4-bit nibbles.
- Can I convert fractional numbers, like a decimal point value?
- No, this tool handles whole numbers only. Fractional base conversion follows a different process involving repeated multiplication and isn't supported here.