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Calcimator

Propagation Delay Calculator

Calculate signal travel time from distance and medium type. Includes transmission delay, RTT, and bandwidth-delay product.

Inputs

km
Mbps
bytes

Results

Propagation Delay

0.334 ms

Total One-Way Delay

0.346 ms

Round-Trip Time

0.691 ms

Propagation Delay333.56 μs
Transmission Delay12 μs
Bandwidth-Delay Product84.37 KB
Propagation Speed299,792.5 km/s
Distance per Bit0.3 m
How to Use This Calculator
  1. Enter the link distance and select the transmission medium (free space, fiber, coax, or microwave).
  2. Enter data rate (Mbps) and packet size (bytes) if transmission delay is also needed.
  3. Review propagation delay in ms and us and transmission delay in us.
  4. Use total one-way delay for latency-sensitive applications like VoIP, trading, and video conferencing.

How the result changes with Distance

DistancePropagation DelayTotal One-Way DelayRound-Trip Time
10,00033.356 ms33.368 ms66.737 ms
35,000116.747 ms116.759 ms233.519 ms
65,000216.817 ms216.829 ms433.657 ms
90,000300.208 ms300.22 ms600.439 ms

What each input means

Distance
Distance between source and destination in kilometers
Transmission Medium
1=Free Space/Air, 2=Coaxial Cable, 3=Fiber Optic, 4=Cat6 Copper
Data Rate
Link data rate in megabits per second
Packet Size
Packet size in bytes (Ethernet MTU = 1500 bytes)

How this is calculated

Formula

Delay = Distance / (c × Velocity Factor)

Worked example, using the default values

  1. Identify Input Parameters
    4 parameters
    Distance = 100, Transmission Medium = 1, Data Rate = 1000, Packet Size = 1500 = 4 input(s) provided
  2. Calculate Propagation Delay
    Propagation Delay
    0.334 = 0.334
  3. Calculate Total One-Way Delay
    Total One-Way Delay
    0.346 = 0.346
  4. Calculate Round-Trip Time
    Round-Trip Time
    0.691 = 0.691
  5. Calculate Propagation Delay
    Propagation Delay
    333.56 = 333.56
  6. Calculate Transmission Delay
    Transmission Delay
    12 = 12

Engine last updated . Checked against 3 independently-derived tests how we verify calculators.

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