How it works

From six answers to a calendar

1. You tell us your goal race, when it is, how you would describe your running, your recent weekly miles and runs, the days and time you have, and whether you have had a recent injury. Optionally, a recent race.
2. The planner checks the goal fits. It simulates a gradual build from your current running and compares where it ends up with the minimums for your goal.
3. You get one of four outcomes: a plan, a plan with a caution, a clear "we can't recommend this" with reasons and alternatives, or a request for missing or corrected answers.
4. The plan is a calendar of rest days and runs, each with an approximate distance and time, an effort description and, if you gave a recent race, an estimated pace range.

The rules every plan follows

These are read straight from the planning engine (version 0.3.1), so this list is always what the product actually does.

• Week 1 never starts above your current weekly mileage. If your time limits cannot hold it, the plan says so.
• Your experience level is checked against your mileage, run frequency and available days. If they disagree, the plan follows the more cautious of the two.
• Mileage rises gradually: a build week adds at most 8% of the last full week (and never more than 2.5 miles). This is a planning heuristic, not a guarantee against injury.
• Every fourth build week is an easier week at about 80% of the previous full week.
• A week adds at most one new stressor: more mileage, an extra running day, or your first harder session. They are never combined.
• The long run grows by at most 15% a week (and at most 1 mile), and is capped by a share of weekly mileage, a distance limit for your goal, and your time limit.
• Most running is easy. There is at most one harder session a week, kept under about 15% of weekly running time and never beyond 25 minutes of hard effort.
• Harder sessions start only for runners with a base: not before week 5, not in easier or taper weeks, not when too few build weeks remain, and never the day before or after the long run.
• Run frequency rises by at most one run every four weeks, and never beyond the days you said you could run.
• Training tapers before the race. Race week is short, easy and includes rest before race day. If the race falls early in the week, the week before it is also a taper week.
• The last long run is at least 6 days before the race, the last tempo or interval session at least 7 days before, and the day before the race is a rest day.
• Pace ranges appear only when you give a credible race or time trial from the last 8 weeks, and only while that result is no more than 12 weeks old. Otherwise the plan uses effort guidance only.
• A finish-time estimate appears only when the plan fits your timeline well, your result is for a distance close to your goal, and the result is still recent on race day. Otherwise the plan gives none.

What it will decline to do

• Plan after a recent injury or pain that limited your running. It cannot judge that safely and suggests seeing a doctor or physical therapist first.
• Plan from a base below 2 runs and 3 miles a week. It suggests building a gentle run-walk habit first.
• Plan a race that is fewer than 4 weeks away.
• Squeeze a goal into a timeline where a gradual build cannot reach the minimum peak week and long run for that distance.

See real examples in Goals our planner declines, and why, or test your own with the race readiness checker.

Limits you should know about

• It trusts what you tell it. It cannot verify your mileage, health or injury history.
• Distances are approximate. They assume an easy pace, either a deliberately slow default for your experience or one from your recent race.
• Pace ranges are estimates. They come from a race-time prediction formula and only appear if you give a race or time trial from the last 8 weeks.
• It does not write run-walk intervals. Walk breaks are allowed on easy runs, but the structure is not planned.
• It does not adapt. A plan is generated once. It does not track what you actually run.
• Distances stop at the half marathon. There are no marathon plans yet.
• It is not coaching. It has not been reviewed by a qualified coach or clinician, and its rules are conservative heuristics, not proven thresholds.

Safety

This plan is general training information, not medical advice and not clearance to exercise. Stop and get professional advice if you feel pain, dizziness, chest discomfort or unusual shortness of breath. If you have a health condition or are unsure whether running is right for you, talk to a doctor first.

Questions