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Rotina Diária

Number Base Converter

Convert between binary, octal, decimal, and hexadecimal—or any base from 2 to 36—with no size limit.

Enter a value in any field—the others update instantly. Negative numbers and numbers of any size are supported.

Processed on your device. Nothing you type is sent anywhere.

How to use: Number Base Converter

  1. Enter a number in any field: decimal, binary, octal, or hexadecimal.
  2. The other fields update as you type.
  3. Use Other base for bases from 2 to 36, and see the bits, bytes, and two's complement for negative numbers.

About this tool

In each base, a digit's position represents a power of that base: in binary, 1011 = 1×8 + 0×4 + 1×2 + 1×1 = 11. In hexadecimal, the letters A through F represent 10 through 15, so FF = 15×16 + 15 = 255. One hexadecimal digit equals exactly 4 bits, which is why colors (#FF8800) and memory addresses use hexadecimal.

Conversions use arbitrary-precision integer arithmetic (BigInt), so numbers with dozens of digits, such as 264 or full hashes, convert without rounding. Prefixes like 0x, 0b, and 0o, along with spaces and underscores, are ignored.

For negative numbers, the tool shows the two's complement using the smallest width that fits the number (8, 16, 32, 64, or 128 bits)—the way processors and languages like C, Java, and C# store signed integers.

Frequently asked questions

How do you convert binary to decimal by hand?

Multiply each digit by 2 raised to its position, counting from zero on the right, then add the results. Example: 1101 = 1×8 + 1×4 + 0×2 + 1×1 = 13.

Does it support decimal numbers?

No. This tool works with integers, the most common use case in programming (bits, colors, permissions, and addresses).

What is base 36 used for?

It uses the 10 digits and 26 letters to create shorter representations. It's commonly used for URL shorteners and compact identifiers.

Is it really free? Is there a daily limit?

It's free with no daily limits. Processing happens on your device, so there's no per-use cost and no need to limit you.

Does it work on phones?

Yes. The site works in any modern browser on Android, iPhone, Windows, Mac, and Linux—no installation needed.

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