Millisecond is 0.001 second units.
Milliseconds to Attoseconds Converter — ms to as
Convert Millisecond (ms) to Attosecond (as) using the exact conversion factor (1 millisecond = 1e+15 attosecond). See the formula, worked examples, and conversion table.
Milliseconds to Attoseconds converter
Converter
Time Converter
Convert SI time, civil time, historical durations, months, and years.
Context values
Some unit families need one extra value for a physically accurate result.
Attosecond is 1e-18 second units.
Result = input x 0.001 / 1e-18.
Months and years use the average Gregorian year.
Reserved above the conversion cards and below the converter.
About Converting Milliseconds to Attoseconds
Millisecond and Attosecond are both everyday units of duration, and converting between them is one of the most routine calculations there is — scheduling, project planning, and billing all depend on it. Specifically: Millisecond is 0.001 second units, and attosecond is 1e-18 second units.
Formula
attoseconds = milliseconds × 1e+15
This factor comes from each unit's defined relationship to the category's base unit: 1 millisecond equals 0.001 base units, and 1 attosecond equals 1e-18 base units, so dividing one by the other gives the direct millisecond-to-attosecond factor of 1e+15.
Simple example
1 ms × 1e+15 = 1e+15 as
1 millisecond = 1e+15 attoseconds.
Real-world example
24 ms × 1e+15 = 2.4e+16 as
24 milliseconds = 2.4e+16 attoseconds.
Conversion table
| Millisecond (ms) | Attosecond (as) |
|---|---|
| 1 ms | 1e+15 as |
| 7 ms | 7e+15 as |
| 24 ms | 2.4e+16 as |
| 30 ms | 3e+16 as |
| 100 ms | 1e+17 as |
| 365 ms | 3.65e+17 as |
Reverse conversion: Attosecond to Millisecond
1e+15 as × 1e-15 = 1 ms
1e+15 attoseconds = 1 millisecond.
milliseconds = attoseconds × 1e-15
For a page dedicated to this direction, see Attosecond to Millisecond.
Understanding the Millisecond (ms)
Millisecond is 0.001 second units.
Understanding the Attosecond (as)
Attosecond is 1e-18 second units.
Reserved between the cards and the FAQ so the page stays balanced.
Frequently asked questions
How many attoseconds are in 1 millisecond?
1 millisecond equals 1e+15 attoseconds, using the exact defined conversion factor rather than an estimate.
How do I convert millisecond to attosecond?
Multiply the millisecond value by 1e+15. The converter above does this instantly to whatever precision you set.
How do I convert attosecond back to millisecond?
Use the reverse factor: 1 attosecond equals 1e-15 milliseconds. You can also use the swap control in the converter above to flip the direction instantly.
What is a millisecond?
Millisecond (ms) is a unit of time.
What is a attosecond?
Attosecond (as) is a unit of time.
Is the millisecond to attosecond conversion exact?
Yes. Both millisecond and attosecond are defined by fixed standards rather than physical artifacts, so the factor of 1e+15 used above is exact to as many digits as you choose to display.