A training plan that knows what your race asks of you

Built for the race almost nobody writes plans for — three legs in 24 hours — and just as happy building for a marathon, a half, a 10k or a 5k. One rule underneath: 80% of your time easy, counted in minutes at effort, anchored to a race you've actually run. Free, no account — the plan lives in your browser.

1 The goal

however far out — the plan uses the whole runway, no cap
as long as you want; race day wins if both are set
the plan rates your odds — paces stay honest either way
sets the race clock (night legs), not your paces
average across your legs, per mi — the plan rates your odds

2 Your fitness

no recent race? run 5k hard and use that
a second race at a different distance fits your personal endurance curve

Age and gender never change your paces — they set realistic improvement rates and honest goal ceilings. Like everything on this page, they stay in your browser.

3 Your life

Once it's on screen, every change rebuilds the plan live — watch the projection move.

Nobody writes plans for three legs in 24 hours

Marathon fitness gets you to the start line of a long relay; it doesn't get you through leg three. Relay mode schedules the four things a road plan never asks for — with your actual legs' distance, climb and descent pulled from the same race packs the app ships for Hood to Coast, Cascade Lakes, Bourbon Chase, Ragnar Northwest Passage and Ragnar Road Minnesota.

+6hours

Doubles — run tired on purpose

In the sharpening weeks, Saturday splits in two: a morning run with quality at leg goal pace, then a second run six hours later on legs that aren't fresh. That's your first two legs in miniature, every week.

ft

Downhill legs punish unready quads

If one of your legs drops meaningfully, the plan adds downhill strides and rolling routes — eccentric load on purpose, so free speed on the descent doesn't become a race-ender two legs later.

2AM

You will race in the dark

When the race clock puts one of your legs between 10 PM and 5 AM, every other week one easy run moves to dawn or dusk, headlamp on. Pacing blind by feel is a skill, and it's trainable.

3rd leg

Quality late, on fatigue

Your last leg comes after ~20 waking hours and two hard efforts. Goal paces bake that in — the same fatigue model the app predicts races with — and the doubles train exactly that skill.

What the engine actually is

Paces come from your anchor. A recent race (or hard time trial) sets a Daniels-style fitness score; easy, marathon, threshold and interval paces derive from it. A second race at another distance fits your personal endurance curve on top. No perceived-fitness sliders — if the paces feel wrong, race something and re-anchor.

Race projections respect your mileage. Standard equivalence calculators are well-calibrated up to the half marathon but run 10+ minutes optimistic for most recreational marathoners — endurance is built with volume, not implied by speed (Vickers & Vertosick 2016, 2,300 runners). Projections to distances longer than your anchor here use an endurance exponent driven by weekly mileage, so the marathon number reflects the miles behind it. Goal odds move when your planned volume does — that's the point.

Age and gender set expectations, never paces. Your anchor already says how fast you are. Age and gender (both optional) only shape how fast fitness realistically builds and where the age-graded ceiling sits — a goal beyond ~95% of the age-graded world best gets an honest ~0, not a plan.

Long runways become training cycles, not a slab. Past the final build, the plan organizes extra weeks as repeating cycles — build, tune-up race or time trial, recover — because concentrated blocks with near-term checkpoints beat one endless mixed build, physiologically and psychologically. Each tune-up re-anchors your fitness score and sharpens the goal odds.

Relay goal paces are the app's predictions. Leg windows use the Relay Tracker app's model — Minetti gradient costing over the leg's sampled profile, Riegel endurance scaling, cumulative fatigue (miles, descent, sleep debt, night starts) and weather — so the site and the app never disagree about the same leg. The race clock assumes your teammates' typical 10k and a typical start wave; both are stated on the plan and move only your night legs, not your paces.

General fitness guidance, not medical advice. Build gradually; see a professional if something hurts.