Ratio / Fraction Converter
Convert between percent, per mille, basis points, parts per million, parts per billion and plain ratios.
1 ratio = 1,000,000 parts per million
Most used ratio units
- Percent % 1 % = 0.01 ratios
- Part per million ppm 1 ppm = 0.000001 ratios
- Part per billion ppb 1 ppb = 1 × 10-9 ratios
- Basis point bp 1 bp = 0.0001 ratios
- Part per trillion ppt 1 ppt = 1 × 10-12 ratios
- Per mille ‰ 1 ‰ = 0.001 ratios
- Ratio Base unit
- Part per thousand ppth 1 ppth = 0.001 ratios
- Part per hundred pph 1 pph = 0.01 ratios
- Part per quadrillion ppq 1 ppq = 1 × 10-15 ratios
- Percent mille pcm 1 pcm = 0.00001 ratios
Popular ratio conversions
- Percent to parts per million 1 % = 10,000 ppm
- Parts per million to percent 1 ppm = 0.0001 %
- Parts per million to parts per billion 1 ppm = 1,000 ppb
- Parts per billion to parts per million 1 ppb = 0.001 ppm
- Percent to basis points 1 % = 100 bp
- Basis points to percent 1 bp = 0.01 %
- Per mille to percent 1 ‰ = 0.1 %
- Ratios to percent 1 ratio = 100 %
What is ratio?
Many quantities are pure ratios: a part compared with the whole. They can be written as a decimal (0.05), a percentage (5%), a per mille (50‰), basis points (500 bp) or parts per million (50,000 ppm). All of these are the same number expressed with different multipliers.
Parts per million (ppm) and parts per billion (ppb) describe trace amounts, such as pollutants in air or water or the carbon dioxide in the atmosphere (about 425 ppm in 2025). Finance uses basis points: one basis point is one hundredth of a percent.
Parts per million can be by mass, by volume or by number of molecules; the ratio itself converts the same way in every case.
Ratio units from smallest to largest
Every proportional ratio unit on the site, ordered by size and expressed in ratios.
- Part per quadrillion 1 × 10-15 ratios
- Part per trillion 1 × 10-12 ratios
- Part per billion 1 × 10-9 ratios
- Part per million 0.000001 ratios
- Percent mille 0.00001 ratios
- Basis point 0.0001 ratios
- Per mille 0.001 ratios
- Part per thousand 0.001 ratios
- Percent 0.01 ratios
- Part per hundred 0.01 ratios
- Ratio 1 ratios
All 11 ratio units
Ratios
Frequently asked questions
How many ppm is 1 percent?
1% = 10,000 ppm.
What is a basis point?
One hundredth of a percentage point: 0.01%. A rate cut of 25 basis points is 0.25%.
How many ppb are in a ppm?
1 ppm = 1,000 ppb.