Number Base Converter
Convert numbers between Binary, Octal, Decimal, and Hexadecimal instantly.
Enter any integer into the box to instantly convert it across the four most common mathematical bases used in computer science: Binary (Base 2), Octal (Base 8), Decimal (Base 10), and Hexadecimal (Base 16). The tool automatically detects your selected input base and generates the corresponding outputs simultaneously.
This utility utilizes PHP's arbitrary-precision mathematics engine, meaning it can flawlessly handle extremely large numbers that would normally overflow standard 64-bit hardware integers. Your conversions run strictly on our secure backend and are never logged or saved.
How it works
In standard mathematics, we count in Decimal (Base 10) utilizing the digits 0-9. However, low-level computer hardware and software engineering frequently require different representations of data.
Binary (Base 2): Uses only 0s and 1s. This represents the raw electrical states (off and on) of transistors inside a computer processor. It is incredibly verbose but essential for machine-level logic.
Hexadecimal (Base 16): Uses digits 0-9 followed by letters A-F. Because exactly four binary bits fit perfectly into one hexadecimal character, hex is heavily used by programmers as a human-readable shorthand for binary data (like MAC addresses, IPv6 networks, and memory pointers).
Octal (Base 8): Uses digits 0-7. While largely legacy today, it was popular in early computing (like 12-bit and 36-bit systems) and is still explicitly used in Unix/Linux file permissions (e.g., chmod 777).
Arbitrary Precision: Standard calculators fail when numbers exceed roughly 19 digits. This tool leverages the BCMath extension, treating inputs as mathematical strings, allowing for mathematically perfect conversions of massive cryptographic keys and hashes without scientific notation rounding errors.
Frequently asked questions
Can it convert negative numbers or fractions?
No. This specific tool is strictly designed for non-negative, whole integers. It does not support floating-point numbers (fractions) or negative symbols, as binary representations of negative numbers (like two's complement) depend heavily on the specific bit-width of the target hardware.
Why did I get an "Invalid characters" error?
You likely entered a digit that does not exist in your selected input base. For example, you cannot use the digit "8" or "9" if you told the tool the input is Octal (Base 8), and you cannot use letters if the input is Decimal (Base 10).
Is there a limit to how large the number can be?
While the mathematical engine can handle theoretically infinite numbers, we restrict the raw text input to a maximum of 2,048 characters to prevent server memory exhaustion. This is still large enough to convert massive 4096-bit cryptographic integers perfectly.
Do I need to include the 0x prefix for hex?
No, it is not strictly required. If you explicitly select "Hexadecimal" as the input base, the tool already knows how to parse it. However, if you include common prefixes like `0x` (hex) or `0b` (binary), the tool will safely strip them out before processing.
Is my mathematical input securely handled?
Yes. It is processed securely within volatile memory during the web request and immediately discarded. Absolutely nothing is written to the hard disk or sent to a third party tracking script.
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