How to Convert Fractions and Decimals
Whether you're measuring lumber for a river table, weighing wax for candles, or sizing materials for a craft project, you'll constantly run into fractions and decimals. A tape measure reads 5/8 of an inch, but your digital scale shows 0.625 ounces. This converter bridges that gap instantly.
Fraction to Decimal: The Simple Method
Every fraction is just a division problem. The numerator (top) divided by the denominator (bottom) gives you the decimal. For example, 3/4 means 3 divided by 4, which equals 0.75. Mixed numbers like 2 3/8 work the same way: convert the fraction part (3 divided by 8 = 0.375) and add the whole number to get 2.375.
Decimal to Fraction: Working Backwards
To go the other direction, count the decimal places and put the number over the matching power of 10. 0.25 has two decimal places, so it becomes 25/100. Then simplify by dividing both numbers by their greatest common factor (25), giving you 1/4. Our calculator does all this simplification automatically.
Why Makers Need This
Woodworkers measure in fractions (3/16", 7/32") but CAD software and CNC machines use decimals. Candle makers weigh ingredients on digital scales (decimals) but recipes often list quantities as fractions. 3D printer settings use decimal millimeters, but drill bits are labeled in fractional inches. Having a quick converter on hand saves time and prevents costly measurement mistakes.
Common Fractions Every Maker Should Know
Here are the conversions that come up most often in crafting and making:
- 1/2 = 0.5 — the most basic split
- 1/4 = 0.25 and 3/4 = 0.75 — quarter measurements
- 1/8 = 0.125 — common in woodworking
- 1/16 = 0.0625 — precision craft work
- 1/3 = 0.333... — repeating decimal, common in recipes
Need to calculate material volumes or costs too? Check out our Resin Volume Calculator or Candle Wax Calculator for project-specific math.
Frequently Asked Questions
How do I convert a fraction to a decimal?▼
Divide the numerator (top number) by the denominator (bottom number). For example, 3/4 = 3 divided by 4 = 0.75. If you have a mixed number like 2 3/4, convert the fraction part first (0.75) then add the whole number (2.75).
How do I convert a decimal to a fraction?▼
Write the decimal over a power of 10 based on the number of decimal places, then simplify. For example, 0.75 = 75/100. Divide both by 25 to get 3/4. Our calculator handles this automatically and gives you the fully simplified fraction.
What is a repeating decimal?▼
A repeating decimal has one or more digits that repeat infinitely. For example, 1/3 = 0.333... and 1/6 = 0.1666... These happen when the fraction's denominator has prime factors other than 2 and 5. Our converter flags repeating decimals so you know the decimal representation is approximate.
Why do makers need fraction-to-decimal conversions?▼
Many woodworking measurements use fractions (like 3/8 inch or 5/16 inch), while digital tools and calculators work in decimals. Resin formulas, wax weights, and 3D print dimensions often need quick conversions between the two. This tool makes switching between measurement systems instant.
What are the most common fractions used in crafting?▼
The most common fractions in crafting and woodworking are 1/2 (0.5), 1/4 (0.25), 3/4 (0.75), 1/8 (0.125), 3/8 (0.375), 5/8 (0.625), 7/8 (0.875), and 1/16 (0.0625). These come up constantly when measuring lumber, fabric, and craft materials.
How do I convert inches with fractions to millimeters?▼
First convert the fraction to a decimal (e.g., 3/8" = 0.375"), then multiply by 25.4 to get millimeters (0.375 x 25.4 = 9.525 mm). This is useful when working with international material specs or 3D printing dimensions.
Is 0.333 the same as 1/3?▼
Not exactly. 1/3 = 0.33333... repeating forever. Writing 0.333 is an approximation that rounds to about 33.3%. For most craft projects, 0.333 is close enough, but for precise measurements you may want to keep working in fractions.