Tools
Running tools that are actually useful in training
Three calculators you can use right now: race-based VDOT, pace and finish-time conversion, and runner-friendly heart rate zones.
All tools
Each tool is a standalone page with its own URL, metadata, and direct internal links so Google can crawl them cleanly.
VDOT calculator
Calculate VDOT from a race result and get Daniels pace zones for easy, marathon, threshold, interval, and repetition work.
Open toolRunning pace calculator
Convert between pace, speed, and finish time for any race distance or training segment.
Open toolHeart rate zone calculator
Estimate practical running HR zones to structure easy runs, threshold sessions, and longer workouts.
Open toolWant ChatGPT or Claude to use these numbers automatically?
STAS passes your watch data, training history, and current condition into ChatGPT or Claude, so your plan is built from real workouts instead of generic templates.