Fraction Calculator: Add, Subtract, Multiply & Divide Fractions | Free

A Yes, just enter 5 as 5/1 in the first field and 3/8 in the second. The calculator handles it automatically. 5 minus 3/8 gives you 37/8, which simplifies to 4 and 5/8. This trick works for multiplying a whole number by a fraction too. On mobile, the input fields are smaller—tap carefully to avoid typing into the wrong box.

A That happens when the result is an irrational number or when you're using the conversion mode. For example, 1/3 divided by 2/5 equals 5/6 as a neat fraction. But try 1/7 plus 1/9, and the calculator may display the decimal (0.2539...) because the repeating decimal is too long to show as a clean fraction. You can toggle back to fraction view using the mode switch. Always check which output format is selected.

A Absolutely. If you're measuring drywall or lumber, fractions like 3/8 inch are common. Add 2 3/4 plus 1 5/16 by typing 2/1 + 3/4 first, then adding the result to 1/1 + 5/16. The auto‑simplification keeps your totals in usable form. For decimal output, flip the mode switch to see 4.0625 inches. One tip: always convert mixed numbers to improper fractions before entering.

A That's because 1/3 and 1/2 have different bottoms — denominators, technically. The calculator finds a common denominator (6) behind the scenes. 1/3 becomes 2/6, 1/2 becomes 3/6, adding up to 5/6. With 1/3 + 1/3, the denominator matches already, so no extra step. This is a common gotcha for kids learning fractions at home. Try entering 1/4 + 1/4 next and watch it simplify 2/4 down to 1/2.

A Yes, use the fraction-to-decimal toggle switch on the results display. This works like a currency converter—flip it and your 7/8 becomes 0.875. For travelers calculating exchange rates, this is handy because you can see precise decimal values without mental math. The toggle works both ways too, so you can switch back to fraction view anytime your result shows a decimal.

A Yes, negative fractions work exactly as you'd expect. Enter -3/4 in either field and the calculator applies the sign correctly. For example, -1/2 minus 1/3 gives you -5/6. One thing to watch: if you're subtracting a negative, like 2/3 minus (-1/4), the result becomes 11/12 because two negatives make a positive. The auto-simplifier also reduces the sign properly, so you won't see a negative zero or awkward formatting. Just type the minus sign before the numerator.

A The calculator automatically reduces every result to its lowest terms, so 6/8 displays as 3/4. That's the auto-simplification feature working. If you need the unsimplified version for a recipe or a construction plan, you're out of luck here—this tool always simplifies. For example, 4/8 becomes 1/2, and 10/15 becomes 2/3. Double-check your original numbers before entering them, because the output won't match your intermediate steps. That's normal behavior, not a bug.

A Type the whole part as a fraction first. For 3 1/2, enter 7/2—that's the improper form. If you'd rather not convert mentally, do two steps: add 3/1 and 1/2 to get 7/2, then run your next operation. The calculator won't parse spaces or a separate whole-number box, so stick to slashes and digits only. Paste a value like 5 3/4 directly and it'll throw an error. Practice with 2 2/3 converted to 8/3, then proceed.

A Parents often use this calculator to verify middle school math homework. Type 3/4 into the first box and 1/8 into the second box to check your child's work. The tool shows 7/8 immediately. But remember to have your student write out the least common multiple steps on paper. Teachers want to see that actual process, not just the final output.

A Many assume multiplying fractions needs a complicated cross-multiplication setup on paper. This calculator handles it instantly when you type 2/3 times 4/5. You get 8/15 without finding a common denominator first. Try multiplying three fractions by doing two at a time.