Running

Set a paced breathing rhythm with custom phase timing and live cues, then track the session in your browser with clear formulas and safety limits.

Plan race-week carbohydrate grams from body weight and event length, then split daily targets across loading days, meal blocks and practiced drinks.

Plan fueling for one run or ride from hourly targets and real bottle or fuel portions, with sodium context and a timed intake schedule.

Turn a sport-specific lactate threshold heart rate into Joe Friel cycling or running zones, with whole-bpm boundaries and session planning.

Find the Good VO2 max range for an adult age cohort and reference sex, then rate a measured value with exact source-table boundaries.

Estimate flat-equivalent running pace and time from a steady uphill or downhill grade, with an optional same-effort slope comparison.

Calculate heart-rate zones from age or a measured maximum using percentage-of-max or heart-rate-reserve methods and optional session planning.

Predict marathon finish time and pace from an eight-week training block, with study-range context and even-effort checkpoint splits.

Build a race-date marathon schedule from your current base with capped progression, cutbacks and taper weeks plus clear training guardrails.

Estimate VO2 max from four field-test methods and compare aerobic capacity with adult age-sex reference bands, METs, and oxygen use.

Convert running pace and speed between metric and imperial units, with constant-speed times for common distances and optional custom splits.

Build a race pace band with cumulative checkpoints and adjustable pacing, including stop-time planning and display-only rounding controls.

Estimate race finish time from distance and pace or speed, then compare splits, planned stops, pacing profiles, and cutoff margin.

Predict a race finish from a recent result using the Riegel formula, then compare condition scenarios with target paces and even splits.

Build race pace and finish-time plans from a goal, recent result, or training block with stop-aware splits and scenario comparisons.

Track live race laps or review pasted splits with pace-by-segment comparisons and finish-time checks across kilometre, mile or 100 m views.

Plan run-walk intervals from route distance and separate segment paces, including exact finish clipping plus marker-stop and cue-load checks.

Calculate your running age grade with the 2025 road tables and find the finish time and average pace needed for a chosen percentage.

Turn a recent race result into estimated training paces, with repetition split times and equivalent race performances for comparison.

Calculate a target heart-rate window from age or a known maximum, compare percent-max and Karvonen methods, and check a current reading.