The Fiber Performance Calculator helps network engineers and technicians calculate the Optical Link Budget for fiber optic cables. It determines if a fiber link is within acceptable loss limits based on length, splices, connectors, and safety margins. It measures both one-way latency and round-trip time (RTT), factoring in the speed of light in fiber and delays from network equipment such as routers and switches. This. The FBB Calculator is a simple yet powerful online tool that calculates the total fiber optic link loss (in decibels, dB) by factoring in losses caused by: By entering these values, users can instantly determine the total loss for a fiber optic link, enabling better system design, troubleshooting. Use this worksheet to input values for all variables that will impact your system's performance.