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Fiber distance calculator
Optical power budget, per-element losses and the maximum run that still closes with margin. Runs entirely in your browser — no project or account is required.
Link
Fiber type
Distance (km)
Tx power (dBm)
Rx sensitivity (dBm)
Connectors0.5 dB each
Splices0.1 dB each
Safety margin (dB)Reserve for ageing, dirt and repairs.
Power budget23.0 dB
Total loss5.70 dB
Margin14.30 dBLink closes
Max distance50.9 km
Loss budget
Closes
- Fiber attenuation
- 3.50 dB
- Connector loss
- 2.00 dB
- Splice loss
- 0.20 dB
- Received power
- -5.70 dBm