Splitr
What's inside
Every feature, explained.
Splitr was built for one thing: getting you from any two running values to all four as fast as possible.
Real-time results — no submit button
Enter any two of speed, pace, distance, or time and every remaining field fills in instantly as you type. Splitr tracks which two values you entered last (the "anchor" fields) and automatically derives the rest. Change one anchor and only the derived fields update — your other input stays locked.
Imperial and metric at the same time
Speed shows mph and km/h simultaneously. Pace shows min/mile and min/km side by side. Distance shows miles and kilometers. No unit toggle, no settings screen — both systems are always visible so you can share results with anyone.
7 race-distance chips, one tap
Quick-tap buttons for the most common race distances: 800m, 1.5K, 3K, 5K, 10K, Half Marathon, and Marathon. Tap any chip and the distance field fills immediately, triggering a recalculation across all other fields.
Type the way you think
Bare numbers are interpreted as pace — type "830" and Splitr reads 8:30 min/mile. Partial times like "130" become 1:30. Standard formatted input (8:30, 1:30:00) works too. The parser handles centisecond precision, so 8:30.5 is valid.
Clear buttons on every field
Each field has its own clear button. Tap to wipe a single value without resetting the whole calculator. The anchor system recalculates remaining fields from whatever two values are still present.
Name, save, and restore any calculation
Tap the save button to name and store the current set of values as a preset. Long-press any preset to rename it inline. Drag to reorder your list. One tap restores a preset and populates all fields instantly — your Marathon PR, 5K goal, or track workout pace is always one tap away.
Presets follow you across devices
All saved presets sync automatically over iCloud. Add a preset on your iPhone and it appears on your iPad. No account to create, no login to manage — iCloud handles everything in the background.
Centisecond accuracy
Time fields support centisecond precision (HH:MM:SS.cc), so you can work with splits at the level that track timing mats record. No rounding to the nearest second.
You feel the calculator working
Subtle haptic pulses confirm when the calculator auto-populates derived fields and when distance shortcuts are activated. Feedback is lightweight — informative, not intrusive.
Free with optional Pro
Splitr is free to download and use. An optional Pro upgrade unlocks unlimited saved presets and additional features as they ship.
Ready to run faster?
Free download on iOS and Android.