Common Denominator Calculator

To add or compare fractions you first make the denominators equal. Enter two fractions — get the least common denominator, both rewritten fractions, and the simplified sum and difference.

📈 LCD via GCD

lcm(a,b) = |a·b| / gcd(a,b).

🧐 Equivalent forms

See both fractions rewritten.

🔢 Sum & difference

Results always reduced.

✓ Step shown

Follow the multiplier logic.

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