Number Base Converter
The Number Base Converter turns a whole number into binary, octal, decimal, and hexadecimal at the same time. Type in any field and the rest update instantly — perfect for programming, digital electronics, networking, and computer-science homework. Every value here is read using positional (place-value) notation: each digit's contribution is the digit itself times the base raised to its position, counting from 0 on the right — decimal 42 is 4×10¹ + 2×10⁰, and its binary form 101010 is 1×2⁵ + 0×2⁴ + 1×2³ + 0×2² + 1×2¹ + 0×2⁰, both summing to the same value. The converter derives each target representation with the standard divide-and-remainder method: repeatedly dividing by the target base and reading the remainders from last to first. Hexadecimal reuses six extra symbols (A–F) to pack the remainders 10–15 into a single digit, which is why it represents the same value in far fewer characters than binary.
Type a whole number in any field — the others convert instantly.
Converts whole numbers between binary, octal, decimal, and hexadecimal. Everything runs in your browser — nothing is uploaded. Values are limited to safe integers (up to 9,007,199,254,740,991).
How This Tool Works
Type a whole number into any field — binary, octal, decimal, or hexadecimal — and the other three convert instantly. Copy any result with one click.
Formula & Method
Each value is read as an integer in its own base (binary is base 2, octal base 8, decimal base 10, hexadecimal base 16) and re-expressed in the others by repeatedly dividing by the target base and reading the remainders.
Example Calculation
Enter 255 in the Decimal field: Binary shows 11111111 (255 = 128+64+32+16+8+4+2+1, every bit set), Octal shows 377 (255÷8 = 31 r7, 31÷8 = 3 r7, 3÷8 = 0 r3, read bottom-up), and Hexadecimal shows FF (255 = 15×16 + 15, with each 15 rendered as the digit F).
Frequently Asked Questions
How do I convert binary to decimal?+
Type your binary number (only 0s and 1s) into the Binary field — the Decimal field updates instantly with the converted value.
What number sizes are supported?+
Any non-negative whole number up to 9,007,199,254,740,991 (the largest integer JavaScript can represent exactly), which covers virtually all everyday and programming needs.
Does it handle decimals or negative numbers?+
This converter works with non-negative whole numbers. Fractions and negative values aren’t supported.
Why does hexadecimal use letters like A–F?+
Base 16 needs sixteen distinct digit symbols, but only 0–9 exist as single decimal digits. Hexadecimal borrows A, B, C, D, E, and F to represent the values 10 through 15 in a single character, which is why FF is what the converter shows for decimal 255 instead of a longer run of digits.
Can I convert a full 64-bit value?+
Not entirely. The converter is limited to JavaScript safe integers — up to 9,007,199,254,740,991 (2^53 − 1) — so it covers the vast majority of everyday and programming use cases, but it can't represent the full 64-bit range (up to roughly 1.8×10^19), which would require exact big-integer handling this tool doesn't do.
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<a href="https://everyfix.net/tools/number-base-converter/">Number Base Converter</a> by <a href="https://everyfix.net">EveryFix</a>Related Tools
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