Finish thedistance
Drop in a GPX and your training, and one race page turns it into your whole hundred. Built around your course, read from your own runs, so you finish without blowing up at mile 60.
- Pacing by grade, not one flat goal pace
- Fueling by the hour, carbs, fluid, and salt for your weight
- Drop bags and crew sheets, printable for race morning
- Cutoff margins, so you see where the day gets tight
Private beta · Garmin · Coros · Suunto coming · No spam
Built by a runner who kept blowing up in the back half, for runners who won't.
Your fitness, projected to race day
One curve reads the work. Fitness rising, fatigue clearing, form landing in the window you want on the start line. The dashed line is your plan, projected forward.
* Projected from your own runs at matching grades, degraded mile by mile for ultra fatigue. A projection, not a promise.
Build your whole hundred in one place
Course, pacing, fueling, drop bags, crew, cutoffs. One race page turns a GPX and your training into the whole operation, read from your own runs, not a generic table.
200 cal + 16 oz every aid from mile 15
Bank nothing before Robinson Flat. Your 5 to 9% climbs run 11:40/mi off current fitness, so hold there or pay for it at mile 60. The race starts at Foresthill, mile 62, when the big canyons begin.
Three rules. Hold 18:30/mi or slower on any pitch over 8% before mile 20. Take 200 calories and 16 oz every aid from mile 15. And in the canyons, run the downs by effort. If your quads are smoked, hike them rather than blowing up before the line.
THE OPERATION
MI 36.8 · 17:08 ARRIVAL
- ▸Spare socks · injinji × 2
- ▸Glide + chamois butter
- ▸Caffeine gels × 6
- ▸500 cal solid food
- ▸Long sleeve · merino base
- ▸Headlamp + spare battery
- ▸Watch charger · cable
- ▸Toothbrush · floss
⏵ The principles
Three things we never fake
Evidence over vibes
Every number traces back to your own runs. No generic tables, no borrowed averages, no guesswork dressed up as science.
A projection, not a promise
We show the math and the margin: your projected finish, your cutoff cushion, and where the race is most likely to come apart.
Built for the dirty distance
Vert, heat, night sections, drop bags, and cutoffs come first. This is a tool for the back half of a hundred, not a 5K PR.
Three steps to the start line
- 01Read only · 30s
Connect your watch
Garmin, Coros, or Suunto. Read only, thirty seconds. Your whole history streams in and stays in sync, and new runs show up on their own.
- 02CTL · ATL · TSB
We read the load
Your fitness curve, your paces by grade, true best splits, and the patterns in your notes. Built from every run, not just the last one.
- 03Built for the course
Your race forecast
A projection built for your course, a polarized plan to race day, an AI brief, and the drop bag and crew sheets that win ultras.
Built honest, in the open
“I kept finishing the back half of hundreds wrecked, with a watch full of data I couldn't read. Summit Line is the instrument I wanted. It reads the work so you can run on evidence, not vibes.
Honest numbers, founder rate
Free during private beta. Here's what it costs after, and what founders pay forever for backing an independently built tool.
Questions, answered straight
Is my data safe?
Summit Line connects to your watch account with read only access. We never change your activities and never sell your data. Disconnect any time and your data goes with you.
What distances is it for?
Anything, but it earns its keep on the long stuff: 50Ks to hundred milers, big vert, heat, night sections, and cutoffs. The projection and pacing model is built around your course.
Is it a coach?
No. It is instruments. It reads your training and projects your race so you can make your own calls. The AI brief is a second opinion, not a prescription, and it is not medical advice.
What does it cost?
Free during private beta. After that, a free tier plus one paid tier, with a founder rate locked forever for early supporters. No countdown timers, no fake scarcity.