Decimal to Octal

Enter a decimal number and convert it to octal, hexadecimal, and binary. Results appear instantly in your browser.

Decimal
Valid: 0-9 (integers)
Octal (Base 8)
Result will appear here
Hexadecimal (Base 16)
—
Binary (Base 2)
—
Quick Reference
0→0
1→1
7→7
8→10
15→17
16→20
64→100
255→377
493→755
511→777

Decimal to Octal Converter

This tool converts decimal (base 10) numbers into their octal (base 8), hexadecimal (base 16), and binary (base 2) equivalents. It is useful when setting Unix file permissions, working with legacy systems, or studying number system conversions.

The conversion runs entirely in your browser using JavaScript's BigNumber library for precision.

How to use

  1. Type or paste a decimal number into the input field (e.g. 255 or 493).
  2. Click Convert to see the octal, hexadecimal, and binary results.
  3. Use the Copy button to copy the octal result to your clipboard.
  4. Click Clear to reset all fields.

What is octal?

Octal is a base 8 number system using the digits 0 through 7. It is used in computing as a compact representation of binary numbers — each octal digit corresponds to three binary digits. Unix file permissions, for example, are commonly expressed in octal (e.g. 755 means read/write/execute for owner, read/execute for group and others).

Example

Decimal:     493
Octal:       755
Hexadecimal: 1ED
Binary:      111101101

MCP integration

MCP (Model Context Protocol) lets AI agents and apps discover and run Coding.Tools utilities for repeatable conversions, formatting, hashing, and generation workflows.

MCP tool name: decimal-to-octal

MCP endpoint: https://coding.tools/mcp

Call tools/list first. Each tool entry includes inputSchema, outputSchema, and examples so an AI agent or client can build valid arguments without guessing.

For tools/call, read result.content[0].text for the display value and result.structuredContent for machine parsing. Tool-level failures return isError: true; protocol failures return a JSON-RPC error.

Example tools/call request:

curl -s https://coding.tools/mcp \
  -H "Content-Type: application/json" \
  -H "Accept: application/json" \
  -H "MCP-Protocol-Version: 2025-06-18" \
  -d '{"jsonrpc":"2.0","id":1,"method":"tools/call","params":{"name":"decimal-to-octal","arguments":{"input":"493"}}}'

Most text and data tools accept an input string plus optional options. Browser-only image tools are listed for discovery and return a web UI link when they need browser image APIs.