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Runs in your browser — nothing you paste is uploaded.

Number Base Converter

Convert an integer between binary, octal, decimal and hexadecimal. Auto-detects 0x/0o/0b prefixes and handles arbitrarily large integers. Runs in your browser.

Input is read in the selected base (Auto uses the prefix, else decimal).


    

  

  
  

    
What it does

    
Enter a whole number and see it in base 2 (binary), 8 (octal), 10 (decimal) and 16 (hexadecimal) at once. In Auto mode a 0x, 0o or 0b prefix picks the input base; otherwise it's read as decimal.

    
Big integers

    
Conversion uses BigInt, so values far beyond 2⁵³ stay exact — handy for 64-bit IDs, bitmasks and hashes.

    
Privacy

    
Everything runs locally; nothing is uploaded.

  


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