Convert Milliliter to Drop
Convert milliliters to drops instantly. 1 milliliter = 20 drop — use the live calculator, the exact formula, a conversion table and worked examples. Also check the Drop to Milliliter converter for the reverse conversion.
Units explained
Milliliter
A milliliter is one thousandth of a liter, exactly equal to one cubic centimeter.
Formed with the SI prefix milli- applied to the liter.
The standard small-volume unit in cooking, medicine and the laboratory.
Metric prefix system.
Drop
A drop is a nominal small volume of about 0.05 mL; the exact size varies with the liquid and dropper.
Standardized loosely in pharmacy as roughly 1/20 of a milliliter (the metric drop).
Used for liquid medication and flavor dosing; treat as approximate.
Pharmacy convention.
Milliliter to Drop conversion formula
Note: this conversion uses a generally accepted modern value. Historical and regional definitions of this unit varied across times and places.
The relationship between milliliters and drops:
To convert milliliters to drops, multiply the value in milliliters by 20. To reverse, multiply drops by 0.05.
How to use this converter
Type a value into the calculator. The result in drops updates as you type. Tap a quick value, copy the result with one click, or use the swap arrow to jump straight to the Drop to Milliliter converter for the reverse direction.
Step-by-step: convert milliliters to drops
- Write down the value in milliliters (mL).
- Multiply that value by the factor 20.
- The product is the equivalent value in drops (gtt).
- To reverse, multiply the drop value by 0.05.
Worked examples
Example 1 — Convert 1 mL to gtt:
1 × 20 = 20 gtt
Example 2 — Convert 100 mL to gtt:
100 × 20 = 2000 gtt
Real-world example — Infrared to visible-spectrum mapping
A 10-milliliter thermal infrared wavelength corresponds to a much larger number in drops, the unit favoured for ultraviolet and visible-light specifications.
10 mL × 20 = 200 gtt
Real-world example — Mid-micron to nanometer
3 milliliters equals 3,000 drops — useful when relating mid-infrared wavelengths (typically quoted in microns) to nanometer-scale visible-light wavelength tables.
3 mL × 20 = 60 gtt
Real-world example — From microns to sub-micron features
One milliliter equals one thousand drops — the conversion semiconductor designers do constantly when comparing mask feature dimensions to actual transistor gate lengths.
1 mL × 20 = 20 gtt
Milliliter to Drop conversion table
Standard reference values for converting milliliters to drops:
| Milliliter [mL] | Drop [gtt] |
|---|---|
| 0.01 | 0.2 |
| 0.1 | 2 |
| 1 | 20 |
| 2 | 40 |
| 3 | 60 |
| 4 | 80 |
| 5 | 100 |
| 10 | 200 |
| 20 | 400 |
| 30 | 600 |
| 40 | 800 |
| 50 | 1000 |
| 100 | 2000 |
| 500 | 10000 |
| 1000 | 20000 |
Frequently asked questions
How many drops is 1 milliliter?
How do I convert milliliters to drops?
How do I convert drops back to milliliters?
How many drops is 100 milliliters?
Popular volume unit conversions
Convert Milliliter to other volume units
Show all Milliliter conversions
Metric / SI (13 units)
US Customary (Liquid) (15 units)
US Customary (Dry) (5 units)
Imperial (UK) (14 units)
Cubic (length-derived) (4 units)
Cooking / Culinary (5 units)
Sources & references
Conversion factor (1 mL = 20 gtt) verified against the following authoritative sources:
- BIPM — The International System of Units (SI Brochure 9th ed.)
Official BIPM publication defining the seven SI base units (including the meter) and the rules for their use. The global authority on units of measurement.
- NIST — Guide to the SI
US National Institute of Standards and Technology reference covering the SI base and derived units with definitions and usage rules for US technical practice.
- NIST Special Publication 811 — Guide for the Use of the International System of Units
Detailed NIST guide covering exact conversion factors between SI and US customary units along with formatting and rounding conventions.
- NIST — Refinement of values for the yard and pound (Federal Register 1959)
The treaty (signed by US
- International Astronomical Union — System of Astronomical Constants
The IAU defines astronomical units including the AU (149597870700 m exactly) light-year and parsec used in astronomy and astrophysics.