Convert Attogram to Milligram
Convert attograms to milligrams instantly. 1 attogram = 1e-15 milligram — use the live calculator, the exact formula, a conversion table and worked examples. Also check the Milligram to Attogram converter for the reverse conversion.
Units explained
Attogram
An attogram (ag) equals 10^-21 kilogram.
From the SI prefix 'atto-' (from Danish 'atten', eighteen).
Frontier nanoscience and single-molecule mass detection.
The atto- prefix was adopted by the CGPM in 1975.
Milligram
A milligram (mg) equals one-millionth of a kilogram, or 0.001 gram.
From the SI prefix 'milli-' (from Latin 'mille', thousand).
Standard for medicine dosing, nutrition labels, and fine jewelry.
Part of the original metric system of 1795.
Attogram to Milligram conversion formula
The relationship between attograms and milligrams:
To convert attograms to milligrams, multiply the value in attograms by 1e-15. To reverse, multiply milligrams by 1e+15.
How to use this converter
Type a value into the calculator. The result in milligrams updates as you type. Tap a quick value, copy the result with one click, or use the swap arrow to jump straight to the Milligram to Attogram converter for the reverse direction.
Step-by-step: convert attograms to milligrams
- Write down the value in attograms (ag).
- Multiply that value by the factor 1e-15.
- The product is the equivalent value in milligrams (mg).
- To reverse, multiply the milligram value by 1e+15.
Worked examples
Example 1 — Convert 1 ag to mg:
1 × 1e-15 = 1e-15 mg
Example 2 — Convert 100 ag to mg:
100 × 1e-15 = 1e-13 mg
Real-world example — Sub-visible-light wavelength
500 attograms (the green-yellow visible band) equals 0.5 milligrams — the canonical conversion in optics between wavelength specifications and micron-scale lens-coating thicknesses.
500 ag × 1e-15 = 5e-13 mg
Real-world example — Spanning sub-micron to micron scale
Crossing from attograms to milligrams is the everyday workflow of microscopy and semiconductor engineering — a measurement of 1000 attograms translates to a much more compact value in milligrams that fits the scale of biological cells and process nodes.
1000 ag × 1e-15 = 1e-12 mg
Attogram to Milligram conversion table
Standard reference values for converting attograms to milligrams:
| Attogram [ag] | Milligram [mg] |
|---|---|
| 0.01 | 1e-17 |
| 0.1 | 1e-16 |
| 1 | 1e-15 |
| 2 | 2e-15 |
| 3 | 3e-15 |
| 4 | 4e-15 |
| 5 | 5e-15 |
| 10 | 1e-14 |
| 20 | 2e-14 |
| 30 | 3e-14 |
| 40 | 4e-14 |
| 50 | 5e-14 |
| 100 | 1e-13 |
| 500 | 5e-13 |
| 1000 | 1e-12 |
Frequently asked questions
How many milligrams is 1 attogram?
How do I convert attograms to milligrams?
How do I convert milligrams back to attograms?
How many milligrams is 100 attograms?
Popular weight unit conversions
Convert Attogram to other weight units
Show all Attogram conversions
Metric / SI (17 units)
Avoirdupois (15 units)
Troy & Apothecary (10 units)
Indian / South Asian (6 units)
Scientific / Atomic (9 units)
Astronomical (4 units)
Biblical / Ancient (14 units)
Sources & references
Conversion factor (1 ag = 1e-15 mg) 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.