Mass and Weight · Unit Converter

Convert Attogram to Femtogram

Convert attograms to femtograms instantly. 1 attogram = 0.001 femtogram — use the live calculator, the exact formula, a conversion table and worked examples. Also check the Femtogram to Attogram converter for the reverse conversion.

Written by Sunith Babu L, Ph.D., Lead Engineer Reviewed by Dr. Ashok Kumar K, Ph.D.
Mass and Weight category 2 min read Published Last reviewed Updated

Units explained

Metric / SI

Attogram

What is a attogram?

An attogram (ag) equals 10^-21 kilogram.

Origin of the attogram

From the SI prefix 'atto-' (from Danish 'atten', eighteen).

Where it is used

Frontier nanoscience and single-molecule mass detection.

When and where it was developed

The atto- prefix was adopted by the CGPM in 1975.

Metric / SI

Femtogram

What is a femtogram?

A femtogram (fg) equals 10^-18 kilogram.

Origin of the femtogram

From the SI prefix 'femto-' (from Danish/Norwegian 'femten', fifteen).

Where it is used

Nanotechnology and high-sensitivity mass spectrometry.

When and where it was developed

The femto- prefix was adopted by the CGPM in 1975.

Attogram to Femtogram conversion formula

The relationship between attograms and femtograms:

1 ag = 0.001 fg
1 fg = 1000 ag

To convert attograms to femtograms, multiply the value in attograms by 0.001. To reverse, multiply femtograms by 1000.

How to use this converter

Type a value into the calculator. The result in femtograms updates as you type. Tap a quick value, copy the result with one click, or use the swap arrow to jump straight to the Femtogram to Attogram converter for the reverse direction.

Step-by-step: convert attograms to femtograms

  1. Write down the value in attograms (ag).
  2. Multiply that value by the factor 0.001.
  3. The product is the equivalent value in femtograms (fg).
  4. To reverse, multiply the femtogram value by 1000.

Worked examples

Example 1 — Convert 1 ag to fg:
1 × 0.001 = 0.001 fg

Example 2 — Convert 100 ag to fg:
100 × 0.001 = 0.1 fg

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 attograms can be re-expressed in femtograms for direct comparison with another instrument's calibration data sheet.

800 ag × 0.001 = 0.8 fg

Real-world example — Molecular dimensions

The diameter of small molecular structures (around 2 attograms) is often converted into related sub-micron units when comparing measurements across different microscopy techniques or imaging modalities.

2 ag × 0.001 = 0.002 fg

Attogram to Femtogram conversion table

Standard reference values for converting attograms to femtograms:

Attogram [ag]Femtogram [fg]
0.011e-5
0.11e-4
10.001
20.002
30.003
40.004
50.005
100.01
200.02
300.03
400.04
500.05
1000.1
5000.5
10001

Frequently asked questions

How many femtograms is 1 attogram?
1 attogram equals 0.001 femtogram.
How do I convert attograms to femtograms?
Multiply the value in attograms by 0.001 to get femtograms.
How do I convert femtograms back to attograms?
Multiply the value in femtograms by 1000, or use the Femtogram to Attogram converter.
How many femtograms is 100 attograms?
100 attograms equals 0.1 femtograms, because 100 × 0.001 = 0.1.

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)
Force / Engineering (5 units)

Sources & references

Conversion factor (1 ag = 0.001 fg) verified against the following authoritative sources:

Results are provided for general reference. Verify critical measurements against an authoritative standard.