For sets without an interval it estimates from your easy pace per 100 plus any rest you note, and shows the total as approximate so you can plan around lane time.
How to write a swim workout
Write one set per line. Start with the number of repeats and the distance, like 4x100 or 8 × 50; a single swim is just the distance, like 400. Add what to swim, such as free, kick, pull, drill, IM or easy. Then add an interval with @, for example @1:45, or a rest with rest 15. Lines like Warm-up, Main set, Kick set, Pull set and Cool-down start a new section, and lines starting with # are notes.
SwimCard totals each section and the whole workout, converts the distance into lengths for your pool and works out the time. Sets on an interval are exact; sets without one are estimated from the easy pace per 100 you enter, so the time is labelled as approximate.
Structuring a good practice
Most workouts follow the same shape: an easy warm-up of 10 to 20 percent of the total, some drill or kick to work on technique, a main set where the real work happens, and an easy cool-down. Keep intervals honest; if you are getting less than five seconds rest on aerobic repeats, add time to the send-off.
Private by design
SwimCard has no server-side processing. Your workout stays in this browser and is saved in local storage on this device only.
Frequently asked questions
What does @1:45 mean in swimming?
Leave every 1 minute 45 seconds. If you finish a 100 in 1:30 you get 15 seconds rest before the next one.
How do I pick my interval?
Take your comfortable 100 time and add 10 to 20 seconds for aerobic sets; less rest for threshold work.
What is the difference between interval and rest?
Interval is a fixed send-off. Rest is a fixed break after each repeat, so faster swimmers finish sooner.
Is SwimCard free?
Yes. Building, totalling, printing and copying workouts is free with no sign-up.
Is my workout stored online?
No. Your workout is saved only in this browser on this device.