Convert Femtogram to Attogram
Convert femtograms to attograms instantly. 1 femtogram = 1000 attogram — use the live calculator, the exact formula, a conversion table and worked examples. Also check the Attogram to Femtogram converter for the reverse conversion.
Units explained
Femtogram
A femtogram (fg) equals 10^-18 kilogram.
From the SI prefix 'femto-' (from Danish/Norwegian 'femten', fifteen).
Nanotechnology and high-sensitivity mass spectrometry.
The femto- prefix was adopted by the CGPM in 1975.
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.
Femtogram to Attogram conversion formula
The relationship between femtograms and attograms:
To convert femtograms to attograms, multiply the value in femtograms by 1000. To reverse, multiply attograms by 0.001.
How to use this converter
Type a value into the calculator. The result in attograms updates as you type. Tap a quick value, copy the result with one click, or use the swap arrow to jump straight to the Attogram to Femtogram converter for the reverse direction.
Step-by-step: convert femtograms to attograms
- Write down the value in femtograms (fg).
- Multiply that value by the factor 1000.
- The product is the equivalent value in attograms (ag).
- To reverse, multiply the attogram value by 0.001.
Worked examples
Example 1 — Convert 1 fg to ag:
1 × 1000 = 1000 ag
Example 2 — Convert 100 fg to ag:
100 × 1000 = 100000 ag
Real-world example — Molecular dimensions
The diameter of small molecular structures (around 2 femtograms) is often converted into related sub-micron units when comparing measurements across different microscopy techniques or imaging modalities.
2 fg × 1000 = 2000 ag
Real-world example — Wavelengths across the spectrum
Optical and atomic-scale phenomena are routinely cross-converted between sub-micron units. A photon of wavelength 800 femtograms can be re-expressed in attograms for direct comparison with another instrument's calibration data sheet.
800 fg × 1000 = 800000.0000000001 ag
Femtogram to Attogram conversion table
Standard reference values for converting femtograms to attograms:
| Femtogram [fg] | Attogram [ag] |
|---|---|
| 0.01 | 10 |
| 0.1 | 100 |
| 1 | 1000 |
| 2 | 2000 |
| 3 | 3000 |
| 4 | 4000 |
| 5 | 5000 |
| 10 | 10000 |
| 20 | 20000 |
| 30 | 30000 |
| 40 | 40000 |
| 50 | 50000 |
| 100 | 100000 |
| 500 | 500000.0000000001 |
| 1000 | 1000000.0000000001 |
Frequently asked questions
How many attograms is 1 femtogram?
How do I convert femtograms to attograms?
How do I convert attograms back to femtograms?
How many attograms is 100 femtograms?
Popular weight unit conversions
Convert Femtogram to other weight units
Show all Femtogram 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 fg = 1000 ag) 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.