Binary to Decimal / Decimal to Binary
Convert values between binary bits (Base 2) and decimal integers (Base 10).
Converter Inputs
Conversion Output
Calculations are computed locally in-browser as you type.
Binary to Decimal / Decimal to Binary
Convert base-2 binary strings to base-10 decimal integers locally in your web browser. Built on client-side arithmetic engines, this tool processes conversions directly in sandbox memory, ensuring that IP address bytes or file permission parameters are never sent to external servers.
Manual Conversion Calculations & Worked Example
Binary numbers use base-2 positional notation, where each digit (bit) represents a power of 2:
- 1Positional Weighting:
Each column in a binary number has a weight starting from the rightmost bit (least significant bit, LSB) moving left:
- 1st column (right): 2^0 = 1
- 2nd column: 2^1 = 2
- 3rd column: 2^2 = 4
- 4th column: 2^3 = 8
- 5th column: 2^4 = 16, and so on.
- 2The Summation Formula:
To convert a binary number to decimal, multiply each bit (d_k) by its corresponding positional weight (2^k) and calculate the sum:
Decimal = sum(from k=0 to n-1) (d_k * 2^k)
Where d_k is the bit value (0 or 1) at index k (counting from 0 on the right).
- 3IP Octet Example Conversion (Binary 11000000):
- 2Bit index 6: 1 * 2^6 = 64
- 3Bit index 7: 1 * 2^7 = 128
- 4All other indices are 0.
- 5Sum: 128 + 64 = 192. (This is the decimal representation of the first octet of a class C IP subnet mask).
[Input Binary String (e.g. 11000000)]
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v
[Map each bit to its positional weight: 128, 64, 32, 16...]
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v
[Multiply bit values by weights and calculate sum]
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v
[Output Decimal Integer (192)]- Subnet Octet: The binary octet
11111111translates to 128+64+32+16+8+4+2+1 = 255. - IP Prefix: The binary string
11000000translates to 128+64 = 192. - Byte Flag: The binary string
10101010translates to 128+32+8+2 = 170.
Encoding & Conversion Standards
- Internet Engineering Task Force (IETF): RFC 4632 on Classless Inter-Domain Routing (CIDR).
- NIST Guide on Unit Representations: Standard representation of binary and digital parameters.
- MDN Web Docs: Math and calculation syntax reference.
Binary to Decimal Converter Online — IP Subnetting & Bit Registers
This utility performs positional notation conversions to translate binary numbers (composed of 0s and 1s) into standard human-readable decimal integers. It processes unsigned binary strings and outputs their decimal equivalence instantly.
- Output Shows NaN: This happens if you enter letters, spaces, or numbers other than
0and1inside the input. Strip all non-binary characters to fix the error. - Result Seems Too Small: Ensure you haven't omitted leading
1bits during copy-paste. - Results Aren't Loading: Ensure JavaScript is enabled in your browser settings.
What is standard dotted-decimal notation?
Dotted-decimal notation is the format used for IPv4 addresses, where 32-bit binary addresses are split into four 8-bit octets and converted to decimal numbers separated by dots (e.g., 192.168.1.1).
How many bits represent a standard subnet mask?
A standard IPv4 subnet mask consists of 32 bits, divided into four 8-bit segments (bytes). The number of leading 1 bits determines the subnet's network prefix length (CIDR).
Are my binary inputs logged?
No. All calculations run locally on your device within your web browser sandbox.
- Decimal to Binary: Convert decimal integers (Base 10) to binary string formats (Base 2).
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- Fahrenheit to Celsius: Convert temperatures from Fahrenheit (°F) to Celsius (°C).
- Meters to Feet: Convert length measurements from Meters (m) to Feet (ft).
Typical Manual Conversion Errors
- Including Non-Binary Characters: Attempting to convert strings that contain characters other than
0and1(like2or letters). The parser will reject these inputs. - Reading Left-to-Right: Calculating positional weights starting from the left instead of the right, resulting in incorrect values.
- Adding Incorrect Powers: Confusing powers of 2 (e.g., assuming 2^3 is 6 instead of 8).
The Allin1Tool Team designs privacy-focused client-side browser utilities for developers, designers, and office professionals.
Last updated & verified: July 8, 2026
Frequently Asked Questions
How does binary-to-decimal conversion work?
Each binary digit is multiplied by 2 raised to the power of its position index (starting from 0 on the right), and the results are summed.
What is hexadecimal notation?
A base-16 numbering system that uses sixteen distinct symbols: 0-9 to represent values zero to nine, and A-F to represent values ten to fifteen.
Are my numeric conversions private?
Yes, all conversion algorithms run locally inside your browser sandbox.