Flight Tracker
Follow any flight live on a map.
Track a flight →Airline fare class charts and mileage calculators
Decode fare classes, calculate the miles you will earn, and track any flight live.
Fare Class Charts
See what each fare letter means and what it earns.
Mileage Calculators
Estimate miles and status credit before you book.
Compare Fare Classes
See airlines side by side.
Compare →Delta Upgrade Priority
See where you stand on the upgrade list.
Check priority →Great Circle Distance
Measure the distance between any two airports.
Measure →Use with AI Assistants
Ask Claude or ChatGPT about fare classes and miles, answered from cwsi.net.
Connect →About cwsi.net
We're frequent flyers who built the tools we wished existed. Every calculator and chart is free; a small membership removes ads and adds extras. Read our story