Compare 2 or 3 fractions using simplification, common denominators, decimals, and cross products. Rank fractions, find the LCD, and visualize which value is largest at a glance.
Comparing fractions sounds simple until the denominators stop matching. Numbers like 5/12, 2/3, and 11/18 cannot be ranked reliably by looking at numerators alone because the pieces are different sizes. The right comparison method is to either rewrite every fraction on a common denominator, convert them to decimals, or use cross multiplication to compare them pairwise. This calculator brings all three views together so you can see the same result from multiple angles instead of trusting one shortcut.
You can compare either two or three fractions, simplify them first, sort them from largest to smallest or the reverse, and inspect exactly how the ordering is obtained. The calculator reports the least common denominator, places every fraction on that shared denominator, shows the decimal and percent form of each value, and highlights which one is closest to common benchmarks like one-half and one whole. That makes it useful not only for homework but also for recipe scaling, measurements, and probability comparisons.
The visual ranking section helps with intuition. Fractions that look close on paper often separate quickly when plotted as decimals or lined up on the same denominator. At the same time, the cross-multiplication table shows the exact arithmetic proof behind each pairwise comparison, which is what teachers usually want to see in written work.
Manual fraction comparison often breaks down into repetitive steps: simplify first, find the LCD, scale numerators, then compare. If you are checking three fractions, you also need to keep the order straight and avoid arithmetic slips. This calculator compresses that workflow into one screen while preserving the structure of the math. It is especially useful when two fractions are close together, when one fraction is improper, or when you want to justify the ranking with both decimal evidence and exact cross products.
If a/b and c/d are fractions with nonzero denominators, compare them by cross multiplication: a*d versus c*b. If a*d > c*b then a/b > c/d; if a*d < c*b then a/b < c/d; and if they are equal then the fractions are equivalent. For comparing several fractions at once, use LCD = lcm(denominators) and rewrite each fraction with that denominator.
Result: 2/3 > 11/18 > 5/12
The LCD of 12, 3, and 18 is 36. Rewriting gives 5/12 = 15/36, 2/3 = 24/36, and 11/18 = 22/36. Since 24 > 22 > 15, the order is 2/3, then 11/18, then 5/12.
A strong mental-math strategy is to compare fractions against familiar benchmarks such as 1/2, 1, and sometimes 3/4. For example, 5/12 is a little below 1/2, 11/18 is a little above 1/2, and 2/3 is clearly above both. This does not replace exact comparison, but it helps you predict the order before checking it with LCDs or cross products.
Cross multiplication works because multiplying both fractions by the product of their denominators preserves the comparison. Instead of comparing a/b and c/d directly, you compare a*d and c*b, which are whole numbers. This avoids rounding and is especially useful when decimals repeat, such as 2/3 = 0.6666....
If you are comparing more than two fractions, or if you also plan to add or subtract them, building one least common denominator is often cleaner. It puts every fraction into the same unit system and makes the ranking visually obvious. That is why the calculator reports both the ordered list and the LCD forms together.
For two fractions, cross multiplication is usually the fastest exact method. Compare a*d to c*b. The larger cross product belongs to the larger fraction.
Once fractions are rewritten with the same denominator, they represent the same size pieces. At that point you only need to compare how many of those pieces each fraction contains, which means comparing numerators directly.
You can, and it is often intuitive, but decimal conversion may hide exact equivalence or rounding differences. That is why this calculator shows both decimal values and exact common-denominator forms.
Yes. Improper fractions are compared the same way as proper fractions. In fact, the table often makes it easier to see whether a value is above or below 1.
Equivalent fractions produce identical cross products and identical values on the LCD. For example, 2/4 and 3/6 both simplify to 1/2.
Because the denominator sets the size of each part. Eighths are bigger pieces than twelfths, so 7/8 can be larger than 9/10 even though 7 is less than 9 only if the underlying piece size is considered correctly.