part per thousand
Concentrationexact by definition
A part per thousand is 0.1%, also written per mille or ‰. Salinity is the classic use: seawater is about 35 ppth, which is the number oceanographers wrote as 35‰ for most of the twentieth century. Blood alcohol limits in much of Europe are set in per mille as well.
Watch out: Modern oceanography abandoned the symbol. Practical salinity has been a dimensionless ratio since 1978 and is written 35 PSU or just 35, deliberately without a unit, because it is defined by conductivity rather than by mass of dissolved solids.
| 1 | 0.1 |
One part per thousand in every concentration unit
| 1,000,000,000 | part per trillion (ppt) | |
| 1,000,000,000 | nanogram per liter (ng/L) | |
| 1,000,000 | parts per billion (ppb) | |
| 1,000,000 | microgram per liter (μg/L) | |
| 1,000 | parts per million (ppm) | |
| 1,000 | part per million by volume (ppmv) | |
| 1,000 | milligram per kilogram (mg/kg) | |
| 1,000 | milligram per liter (mg/L) | |
| 58.418 | grain per US gallon (as CaCO₃) (gpg) | |
| 1 | part per thousand (ppth)this unit | |
| 1 | gram per liter (g/L) | |
| 0.1 | percent (%) | |
| 0.1 | percent by weight (% w/w) | |
| 0.1 | percent by volume (% v/v) | |
| 0.1 | percent weight per volume (% w/v) | |
| 0.001 | fraction (0–1) (fraction) |
Solvers that use concentration