Time Dilation Calculator
Calculate how time slows down for objects moving at relativistic speeds
Time Dilation Results
Proper Time τ (moving)
1.0000 s
1.0000e+0 s
Dilated Time t (stationary)
1.3424 s
1.3424e+0 s
Dilation Factor t/τ
1.342358×
Time Runs Slower By
34.2358%
Velocity (β = v/c)
0.667111408c
Lorentz Factor γ
1.342358
Twin Paradox Example
If a twin travels at this velocity for what they experience as 1 year:
Traveling Twin Ages
1.0000 years
Earth Twin Ages
1.3424 years
Dilation at Various Speeds
| Velocity (%c) | Dilation Factor γ |
|---|---|
| 10.0% | 1.005038× |
| 50.0% | 1.154701× |
| 90.0% | 2.294157× |
| 99.0% | 7.088812× |
| 99.9% | 22.366272× |
About Time Dilation
According to special relativity, time passes more slowly for a moving observer: t = γτ where τ is the proper time (measured by the moving clock) and t is the time measured by a stationary observer. This effect has been confirmed by experiments with muons and atomic clocks on aircraft.
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Editorial Note
MyCalcBuddy Editorial Team
This page is maintained as an educational calculator reference.
Formula Source: University Physics
by Young & Freedman