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Ratio & proportion tools

4:1 Ratio Calculator

A 4:1 ratio has 5 total parts, and the first part is 80% of the whole, the second part is 20% of the whole. The ratio is already in its simplest form.

4:1 drawn to scale

4:1

Simplest form 4:1 · 5 total parts

500
Shares: 80% / 20% of 500.

Exact result

400 units · 100 units

80% : 20% · 5 total parts · 1 part = 100 units

first part — 400 unitssecond part — 100 units
Total parts
5
Simplest form
4 : 1
One part
100 units

Know one side instead?

Enter one measured amount to scale the whole ratio.

Working

  1. Add the parts: 5 total parts.
  2. One part = 500 ÷ 5 = 100 units.
  3. Multiply one part by each ratio part: 400 and 100.

Equivalent 4:1 ratios

  • 4 : 1
  • 8 : 2
  • 12 : 3
  • 16 : 4
  • 20 : 5
  • 24 : 6

What 4:1 means

A 4:1 ratio has 5 total parts. Each part is worth the total divided by 5, so the shares are 80% and 20% of whatever you are dividing.

Total parts
5
Simplest form
4:1
One part of 500
100

Where this ratio shows up

Four times as much of the first quantity, so it makes up four-fifths of the total. Common in render mixes and weighted shares.

Worked example

Dividing 500 in a 4:1 ratio gives 400 and 100. Add them back together and you get 500 exactly — a quick way to check any split.