Design and validate fiber-optic links in seconds. Enter your fiber type, distance, connectors, splices, and components to calculate total optical loss, link margin, and power budget with engineering-grade accuracy.
Add each MUX or DEMUX on the path. Choose a preset for typical insertion loss, or enter a custom value. Passive CWDM/DWDM: 1–6 dB. Active transponders: 0.5–1.5 dB.
This tool helps network engineers, fiber-optic technicians, and link designers quickly determine:
Supports single-mode (SMF) and multimode (MMF) fiber, common wavelengths (850 nm, 1310 nm, 1550 nm), and standard attenuation values — all overridable for custom designs.
Optical path loss is the sum of all attenuation sources in a fiber-optic link:
The calculator applies industry-standard values automatically, or you can override any value for custom designs or field measurements.
Here is a worked example using this calculator:
Use this tool to instantly compute similar scenarios for any fiber-optic link, including CWDM/DWDM paths with MUX/DEMUX insertion losses.
The calculator uses these industry-standard defaults. You can override any value for your specific components.
| Fiber type & wavelength | Typical attenuation | Default used |
|---|---|---|
| SMF — 1310 nm (O-band) | 0.30–0.40 dB/km | 0.35 dB/km |
| SMF — 1550 nm (C-band) | 0.18–0.25 dB/km | 0.25 dB/km |
| MMF OM3 — 850 nm | 2.5–3.5 dB/km | 3.0 dB/km |
| MMF OM4 — 850 nm | 2.0–3.0 dB/km | 2.7 dB/km |
| MMF OM5 — 850 nm | 1.8–2.8 dB/km | 2.5 dB/km |
| Component | Typical loss range | Default value |
|---|---|---|
| Connector (LC/SC, factory polish) | 0.2–0.5 dB | 0.5 dB |
| Connector (field-terminated) | 0.5–1.0 dB | — |
| Fusion splice | 0.02–0.1 dB | 0.1 dB |
| Mechanical splice | 0.2–0.5 dB | — |
| Patch panel (per side) | 0.3–0.75 dB | 0.5 dB |
| CWDM MUX — passive 4 ch | 1.5–2.5 dB | 2.0 dB |
| CWDM MUX — passive 8 ch | 2.5–3.5 dB | 3.0 dB |
| DWDM MUX — passive 40 ch | 4.0–6.0 dB | 5.0 dB |