Guides
Everything you need to compare swimming times across courses, plan paces, and build race splits.
Calculator
Swim Pace Calculator
Turn any total time and distance into target paces per 25, 50, 100 or 200 — in yards or meters.
Calculator
Swim Split Calculator
Break a race goal into even cumulative splits down to every 25 or 50.
Calculator
Critical Swim Speed (CSS)
Run a 400 + 200 test and get your threshold pace, five training zones and projected times.
Calculator
Interval & Send-off Calculator
Build a swim set from repeats, distance and pace — get repeat times and wall-clock send-offs.
Calculator
Swim Speed & Race Projection
Pace per 100m and per 100yd, speed in m/s / km/h / mph, and projected 200–mile times.
Calculator
Swimming Calories Calculator
Estimate calories burned by stroke, intensity, body weight and session time.
Calculator
Swim Lengths to Distance
Convert pool lengths to distance and back for 25 yd, 25 m and 50 m pools.
Conversion
SCY to LCM Conversion
Short-course yards to long-course meters, with distance-event pairings explained.
Conversion
SCY to SCM Conversion
The most common U.S. ↔ international short-course conversion, and why 1.11 works.
Conversion
SCM to LCM Conversion
Same distances, different pool — see how turn count changes an equivalent time.
Conversion
LCM to SCY Conversion
Long-course meters back to short-course yards for U.S. meets and NCAA planning.
Conversion
LCM to SCM Conversion
Reverse the turn advantage to estimate a 25-meter time from your 50-meter pool swims.
Conversion
SCM to SCY Conversion
International short course to U.S. short course, including 400→500 and 1500→1650.
How Swim Time Conversions Work
Understand the three courses
SCY is swum in 25 yards, SCM in 25 meters and LCM in 50 meters. Yards and meters change distance; 25 vs 50 changes the number of turns. Everything else about time conversion follows from these two facts.
Match the events first
Pair the event you swam with the event you are converting to. Most events convert 1:1 (100 Free → 100 Free), but distance freestyle does not: 500 combines with 400, 1000 with 800, and 1650 with 1500.
Scale, then adjust turns
When the lane length changes, scale the time by the distance ratio and add or remove turn time. When only the turn count changes (SCM ↔ LCM), adjust turns only. The tools on this site do all of this for you, but knowing the logic makes results easier to trust.
Treat every result as an estimate
No conversion is exact — turns, breathing, walls and pacing all vary by swimmer. Use the numbers as comparison and planning tools, and always submit official times through the governing body when entries require them.
Quick reference
- SCY → SCM: multiply by 1.11 (near-matching events)
- SCM → SCY: divide by 1.11
- SCM → LCM: add turn time (distance ÷ 50 extra turns × stroke value)
- SCY → LCM: scale by 1.11, then add turn time
- Distance pairings: 500↔400 · 1000↔800 · 1650↔1500
Once you have a target time, build the race with the Pace Calculator, the Split Calculator, and theInterval & Send-off Calculator, and check it against yourCritical Swim Speed.