Which race is faster for you?

Questions

How does the race compare work?

Enter your time on a cool, flat day (a recent race in good weather, or what you would run on a flat course), or switch to your goal. For each race, the course (hills priced mile by mile along the mapped route, and altitude) and one morning's weather (heat, humidity, sun, rain, and wind along the course) are priced with the same engine every racecast.io race page uses. With a cool, flat-day time, each race shows the finish to expect; with a goal, the shape it takes to run that goal there, meaning the time you would need to be able to run on a cool, flat day. Going for a BQ? Pick your age group and the Boston standard becomes your goal. It works for marathons and half marathons, one distance at a time.

What is a typical year, a bad year and the worst year?

Every archived race morning is priced at your pace and ranked by what the weather cost. A typical year is the middle one; when several years cost about the same (within half a percent), it is the one whose temperature is nearest the race's usual. A bad year is the 80th percentile, the 1-in-5 kind, and the worst year is the costliest on record. Each is a real morning, not an average, so the card's numbers are a day that happened and the dot on the history strip is that year.

Which race is cooler?

Each card shows the range of start temperatures across every race morning we have, and the usual one. The history strip below the cards shows what each of those mornings cost at your pace.

Does a 2-minute gap between races matter?

Often less than the weather does. When the gap between the races is smaller than how much a bad year adds at the fastest one, the summary says so: which year you get matters more than which race you pick.

Why does a flat course sometimes lose to a hillier one?

Because the weather varies far more than the hills do. A flat September race that is usually warm and humid can cost more than a rolling spring race that is usually cool. And on a course that climbs and drops about the same, like Boston, the climbs and descents about cancel over the whole race.

What does "Rate my past races" do?

Enter a race, the year and your finish time, and it is turned into a cool, flat-day effort: your time divided by what that morning and course cost. That puts a hot Boston and a cool Chicago on one scale, so you can see which run was really your best, and use that effort as your time to compare the races you are considering next.

What isn't counted?

Crowding, turns, start waves, travel and your own heat training are not in these numbers. Altitude assumes a runner who lives near sea level. A race with few archived mornings shows the course alone until it has enough history for the chosen view.