Binary to Decimal Converter - Convert Base 2 Online

Convert binary to decimal and decimal to binary real-time. Bidirectional conversion with step-by-step explanation. Confidential processing.

Binary → Decimal

Binary (base 2)

Decimal (base 10)

Decimal → Binary

Decimal (base 10)

Binary (base 2)

Quick Reference

Decimal	Binary	Decimal	Binary
0	0	8	1000
1	1	9	1001
2	10	10	1010
3	11	16	10000
4	100	32	100000
5	101	64	1000000
6	110	128	10000000
7	111	255	11111111

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Frequently Asked Questions

Multiply each binary digit by 2 raised to its position (starting from 0 on the right), then sum all values. Example: 1010 = 1×8 + 0×4 + 1×2 + 0×1 = 10.

Up to 53-bit integers (JavaScript safe integer limit). For larger numbers, precision may be lost.

Enter negative decimals normally. For binary, use two's complement representation.

Yes. All conversion happens in your browser using JavaScript. No data is sent to any server.

Computers use binary (base-2) because digital circuits have two states: on (1) and off (0). All data—numbers, text, images—is ultimately stored as binary.

A bit is a single binary digit (0 or 1). A byte is 8 bits. For example, the decimal number 255 is represented as 11111111 in binary (8 bits).

Right to left, each position represents a power of 2: rightmost is 2^0 (1), next is 2^1 (2), then 2^2 (4), 2^3 (8), and so on.

Two's complement is how computers represent negative numbers. Invert all bits and add 1. For example, -5 in 8-bit binary is 11111011.

Yes. Each octet of an IP address (0-255) can be converted to 8-bit binary. For example, 192.168.1.1 becomes 11000000.10101000.00000001.00000001.

Besides binary (base-2) and decimal (base-10), common systems include octal (base-8) and hexadecimal (base-16). Each has uses in computing and mathematics.

Binary → Decimal

Decimal → Binary

Quick Reference

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