Convert Base 7 to Base 3

Convert Base 7 (base 7) to Base 3 (base 3) instantly and accurately.

Selected Base 7 (base 7) - available characters: 0, 1, 2, 3, 4, 5, 6

Base 7 (base 7)
Base 3 (base 3)

Conversion Formula

Step-by-step example using the value 42 (decimal):

Convert Base 7 (base 7) → Base 3 (base 3)

Step 1: Expand each digit of 60 (base 7) by position:

        6 × 7^1 = 42
        0 × 7^0 =  0
        ────────────
        Sum = 42 (decimal)

Step 2: Divide 42 by 3 repeatedly (read remainders upward):

        42 ÷ 3 = 14  r 0
        14 ÷ 3 =  4  r 2
         4 ÷ 3 =  1  r 1
         1 ÷ 3 =  0  r 1
        Read remainders upward: 1120

────────────────────────────
Result:  60 (base 7) = 1120 (base 3)

About Base 7

Septenary (base 7) uses digits 0-6. Each position is a power of 7: 7⁰=1, 7¹=7, 7²=49. Seven is prime, so every fraction p/q (q not divisible by 7) produces a purely repeating expansion. Seven days of the week derive from Babylonian astronomy (the 7 naked-eye celestial objects). Reed-Solomon codes used in QR codes and Blu-ray draw on prime-field properties of GF(7). Conversion: decimal 42 = 6×7+0 = 60₇.

About Base 3

Ternary (base 3) uses digits 0, 1, 2. Each position is a power of 3: 3⁰=1, 3¹=3, 3²=9, 3³=27. Balanced ternary (−1, 0, +1) represents negatives without a sign and minimises rounding error. The Soviet Setun computer (1958) was the only practical balanced-ternary machine. Ternary underlies the Cantor set and Toom-Cook multiplication. Conversion: decimal 42 = 1×27+1×9+2×3+0 = 1120₃.

Quick Reference Table

Base 7 (base 7)Base 3 (base 3)
11
22
512
1122
13101
21120
22121
601120
1212101
20210201
513100110

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