Octal (Base-8) uses digits 0-7. In computing, it's commonly used for Unix/Linux file permissions (e.g. chmod 755). Each octal digit maps to 3 binary digits.

How to convert octal to decimal?

Multiply each digit by powers of 8 (from right, starting at 8⁰) and sum. Example: octal 123 = 1×64 + 2×8 + 3×1 = 83. This tool does it automatically.

What bases are supported?

Binary (Base-2), Octal (Base-8), Decimal (Base-10), and Hexadecimal (Base-16). Enter a value in any base to see all others.

Free Online Octal Decimal Converter

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Updated: 2026-07-12

Number Base Converter

Convert between Binary, Octal, Decimal, and Hexadecimal. Enter a value in any base to see all other representations.

Input type:

Binary (Base-2)

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Octal (Base-8)

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Decimal (Base-10)

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Hexadecimal (Base-16)

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📊 Reference Table (0-32)

Decimal	Binary	Octal	Hex

📖 How to Use

Select input type: Choose the base of your input number.

Enter value: Type a number — all other bases are calculated automatically.

Reference table: Quick reference for numbers 0-32 in all bases.

❓ Frequently Asked Questions

Is Octal Decimal Converter free to use?

Yes, Octal Decimal Converter is completely free to use. No registration or login required — all features are available immediately.

Do I need to install any software?

No. Octal Decimal Converter is a web-based tool — just open it in your browser and start using it. No downloads, plugins, or extensions required.

Does Octal Decimal Converter upload my data to a server?

No. Octal Decimal Converter uses client-side processing — everything runs in your browser. Your data never leaves your device, and the tool works even without an internet connection.

Can I use Octal Decimal Converter on my phone?

Yes. Octal Decimal Converter is fully responsive and works on phones, tablets, and desktops. The interface adapts automatically to your screen size.