Fraction Simplifier
Reduce a fraction to its lowest terms, or simplify an entire list of fractions at once, useful for checking a whole worksheet or dataset in one pass.
One fraction per line, in n/d format.
All calculations run in your browser. Nothing is sent to a server.
Simplifying one fraction is a quick calculation most tools handle fine. Checking a whole worksheet, a dataset of measurements, or a batch of survey ratios one at a time is slower and easy to make a copy-paste error on. This tool also simplifies an entire list at once.
Related Calculators
How It Works
42/56: the greatest common divisor of 42 and 56 is 14, so 42/56 simplifies to 3/4.
How the Batch Mode Handles Edge Cases
Not every line pasted into the batch box is a clean, well-formed fraction. The batch mode skips any line that isn't in a valid n/d format rather than guessing at a correction, so a stray blank line or a typo doesn't silently produce a wrong result mixed in with the correct ones. This matters more than it might seem: a batch tool that quietly "fixes" malformed input can hide a real data entry mistake instead of surfacing it.
Where This Comes Up
Grading and Teaching
A teacher checking a class set of homework answers, all fraction results that should be in lowest terms, benefits from being able to paste in the whole list and see which ones are already simplified and which aren't, rather than checking each one individually.
Working With Ratios and ID Data
Datasets involving ratios (aspect ratios, mixing ratios, survey response ratios) often arrive unsimplified. Simplifying a batch at once makes patterns easier to spot, since equivalent ratios written differently become visibly identical once reduced.
Recipe and Measurement Conversion
Scaling several ingredient measurements in a recipe at once often leaves some fractions unsimplified (like 8/16 instead of 1/2). Simplifying the whole list in one pass is faster than fixing each ingredient line by line.
Checking Work in Bulk
Anyone reviewing a stack of practice problems, a homework set, or exported data containing many fraction values benefits from a single paste-and-check step rather than opening a calculator repeatedly for each one. The batch table format also makes it easy to scan for which fractions were already in lowest terms versus which ones actually needed reducing.
Common Mistakes
Frequently Asked Questions
How do I simplify a fraction?
Find the greatest common divisor (GCD) of the numerator and denominator, then divide both by it. 42/56 has a GCD of 14, simplifying to 3/4.
Can I simplify more than one fraction at once?
Yes. Use the "Batch" mode above and enter one fraction per line. Each one is simplified and shown in a table together.
How do I know a fraction is already fully simplified?
If the greatest common divisor of the numerator and denominator is 1, the fraction is already in lowest terms.
What's the fastest way to find the GCD of two larger numbers?
Breaking both numbers into their prime factors and multiplying together the primes they share is generally faster and more reliable than testing possible common factors one at a time, especially once the numbers get into the hundreds.