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Octal to Binary

Convert octal numbers into binary by expanding each octal digit into its 3-bit binary triplet. Designed for software developers, electrical engineers, students, and computer architecture researchers requiring deterministic client-side accuracy.

Engine: Client-Side Verified (0ms Latency)

Enter valid octal digits (0 to 7).

Calculated Output

Primary Representation
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Step-by-Step Mathematical Proof

Active Derivation
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Concept

What Is Octal to Binary?

Octal to binary conversion translates base-8 numbers into raw binary bits. Each octal digit maps directly to a 3-bit binary triplet without requiring any intermediate decimal conversion.

Methodology

How Does It Work?

Expand each octal digit into its exact 3-bit binary pattern (0=000, 1=001, 2=010, 3=011, 4=100, 5=101, 6=110, 7=111) and concatenate them together.

Formula & Rules

Mathematical Algorithm

d_k \in \{0..7\} \rightarrow [b_2 b_1 b_0]_2 \quad \text{where } d_k = 4b_2 + 2b_1 + b_0
Worked Problem

Step-by-Step Example

Convert 327_8 to binary: 3 -> 011 2 -> 010 7 -> 111 Concatenating yields: 011010111_2 (or 11010111_2 without leading zero).

Important Rules & Edge Cases

  • Each octal digit must expand into exactly 3 binary bits (e.g. 2 is 010, not just 10).
  • Input can only contain digits 0 through 7.

Practical Applications in Engineering

  • Converting chmod octal permissions (e.g., 755) into binary bitmasks (111 101 101).
  • Configuring digital hardware multiplexers and bus selectors.
  • Translating legacy microcode instructions into binary control lines.

Common Mistakes to Avoid

  • Caution: Omitting leading zeros inside individual 3-bit groups (e.g. expanding 1 as 1 instead of 001).
  • Caution: Entering digits 8 or 9.
FAQ

Frequently Asked Questions

What is octal 7 in binary?

Octal 7 is binary 111.