What is Per Mille (?)?
Per mille means "per thousand" and is represented by the symbol ?. It's similar to percentage (%) but uses 1000 as the base instead of 100. One per mille equals 0.1%.
Formula
Per Mille = (Value / Total) x 1,000
When is Per Mille Used?
- Salinity measurements in oceanography
- Blood alcohol content
- Financial calculations (interest rates, taxes)
- Statistical reporting in some countries
- Slope and grade percentages
Examples
Example 1: 35 grams of salt in 1000g of seawater
Permille = (35 / 1000) x 1000 = 35?
Example 2: 5 defects in 500 products
Permille = (5 / 500) x 1000 = 10?
Conversion Guide
- 1? = 0.1%
- 10? = 1%
- 100? = 10%
- 1000? = 100%
Regional Usage
Per mille is commonly used in European countries and scientific contexts. In the US and UK, percentages are more common for the same applications.
Advantages
Per mille provides more precision than percentages when dealing with small proportions, avoiding the need for decimal points.
Quick Tips
- Double-check your inputs for accurate results
- Use parentheses to clarify order of operations
- Results are rounded — consider significant figures
Frequently Asked Questions
Per mille means 'per thousand' - one part in a thousand.
Divide the value by total and multiply by 1,000.
1? = 0.1%
Use ? or type Alt+0137 on Windows.
It's less common in the US but used in scientific contexts.
Multiply the percentage by 10.