Fraction Calculator — Free Online Fraction Math
Add, subtract, multiply and divide fractions with precision.
format_list_numberedShow Step-by-Step Solutionexpand_more
1. Find Least Common Denominator (LCD) of 4 and 2: LCD = 4
2. Convert fractions: (3×1)/(4×1) = 3/4, (1×2)/(2×2) = 2/4
3. Add numerators: 3 + 2 = 5
Final Result: 5/4 = 1.25
Fraction Rules
a/b + c/b = (a+c)/ba/b × c/d = (ac)/(bd)a/b ÷ c/d = a/b × d/cFAQ
Fractions Without the Common-Denominator Fumble
The operations and their rules
Each operation has one rule — mixing them up is where errors live:
| Operation | Rule | Example |
|---|---|---|
| Add / subtract | Common denominator first | 1/3 + 1/4 = 7/12 |
| Multiply | Straight across | 2/3 × 3/5 = 6/15 = 2/5 |
| Divide | Flip the second, multiply | 1/2 ÷ 1/4 = 2 |
| Simplify | Divide both by their GCF | 18/24 → 3/4 |
| Compare | Cross-multiply | 5/7 vs 7/10 → 50 vs 49 |
Where fractions refuse to die
Decimals won the calculator era, but fractions own recipes (¾ cup scaled to 1.5× = 1⅛), construction and tailoring measurements (sooter and inch fractions), exam syllabi from primary through FSc, and anywhere exactness matters — 1/3 is exact, 0.333 is not, and the difference compounds across a calculation. The calculator shows steps, which is the part teachers grade and students actually need.
The supporting cast
Simplification runs on the greatest common factor — the LCM/GCF calculator handles that and the least common denominators addition needs. Fraction-to-percent conversions (3/8 of students = 37.5%) flow through the percentage calculator, and heavier expression work belongs to the scientific calculator.