Time Dilation Calculator

Calculate time dilation effects in special relativity using the Lorentz factor

Calculate Time Dilation

Time interval as measured in the moving reference frame

Velocity must be less than the speed of light (c)

Time Dilation Results

Lorentz Factor (γ)
1.000000
Velocity Fraction
0.0000% of c
Time Ratio
0.000000:1

Dilated Time (Δt')

Years:0.000e+0
Days:0.000e+0
Hours:0.000e+0
Minutes:0.000e+0
Seconds:0.000e+0

Time Difference

Years:0.000e+0
Days:0.000e+0
Hours:0.000e+0
Minutes:0.000e+0
Seconds:0.000e+0

Formula used: Δt' = γ × Δt = Δt / √(1 - v²/c²)

Where: Δt' = dilated time, γ = Lorentz factor, Δt = proper time, v = velocity, c = speed of light

Twin Paradox Example

Space Travel Scenario

Traveling twin: Takes a 10-year journey at 0.8c

Earth-bound twin: Stays on Earth

Velocity: v = 0.8c (80% speed of light)

Proper time: Δt = 10 years (traveling twin's clock)

Calculation

γ = 1 / √(1 - v²/c²) = 1 / √(1 - 0.8²) = 1 / √(1 - 0.64)

γ = 1 / √(0.36) = 1 / 0.6 = 1.667

Δt' = γ × Δt = 1.667 × 10 years

Result: 16.67 years pass on Earth

Age difference: 6.67 years

Velocity References

Everyday Speeds

Car highway: ~0.00000003c

Jet aircraft: ~0.0000003c

Earth orbit: ~0.0001c

Space Technology

Parker Solar Probe: ~0.0006c

Voyager spacecraft: ~0.00006c

Ion drive: ~0.00002c

Theoretical Speeds

0.1c: Noticeable effects

0.5c: Significant dilation

0.9c: Extreme effects

0.99c: Time nearly stops

Physics Constants

Speed of Light (c):299,792,458 m/s
Light speed (km/s):299,792.458 km/s
Light year:9.46 × 10¹⁵ m

Note: Time dilation becomes significant only at very high speeds (>10% of c)

Understanding Time Dilation

What is Time Dilation?

Time dilation is a phenomenon predicted by Einstein's special theory of relativity where time passes differently for observers moving at different velocities relative to each other. As an object approaches the speed of light, time slows down relative to a stationary observer.

The Twin Paradox

The famous thought experiment involves identical twins where one travels to space at high speed while the other remains on Earth. When the traveling twin returns, they will have aged less than their Earth-bound sibling due to time dilation.

Real-World Applications

  • GPS satellites must account for time dilation
  • Particle accelerator experiments observe time dilation
  • Cosmic ray muons reach Earth due to time dilation

The Mathematics

Δt' = γ × Δt

γ = 1 / √(1 - v²/c²)

  • Δt': Time measured by stationary observer (dilated time)
  • Δt: Time measured by moving observer (proper time)
  • γ (gamma): Lorentz factor
  • v: Velocity of moving observer
  • c: Speed of light in vacuum

Important: Time dilation only becomes significant at speeds approaching the speed of light. At everyday speeds, the effect is negligible.

Key Principle

Time is not absolute but depends on the observer's reference frame and relative motion.

Speed Limit

Nothing with mass can reach or exceed the speed of light. As v approaches c, γ approaches infinity.

Experimental Proof

Time dilation has been confirmed countless times in particle physics experiments and GPS technology.