Free race-pacing tool · No account needed
Know your race
before you run it
Pick your race, set a target finish time, and get a checkpoint-by-checkpoint plan — arrival clocks at every aid station, cutoff margins, and where the course will actually be slow. Built on grade, altitude and fatigue modelling, the same engine behind TrailUP training plans.
A real 40-hour simulation of the Swiss Alps 100 — 160 km, 10,150 m of climbing, 17 checkpoints.
Step 1
Pick your race
Every course is mapped by hand — real aid stations, real cutoffs, real terrain.
Brazil · 11–14 Nov 2026
3/6 CP
Mons Ultra Trail
6 races
· 12–318 km Show Hide
Brazil · 11–14 Nov 2026
3/6 CP China · 13–15 Nov 2026
KOLON SPORT Ultra-Trail® Ninghai
3 races
· 25–101 km Show Hide
China · 13–15 Nov 2026
Japan · 14 Nov 2026
KUMAGAWA REVIVAL TRAIL
2 races
· 97–155 km Show Hide
Japan · 14 Nov 2026
China · 14–15 Nov 2026
The Ultra-Trail Xihong autumn
5 races
· 37–99 km Show Hide
China · 14–15 Nov 2026
South Korea · 14 Nov 2026
Gachang trail takeover 54K
Spain · 13–15 Nov 2026
3/5 CP
Costa Blanca Trails
5 races
· 17–102 km Show Hide
Spain · 13–15 Nov 2026
3/5 CP Croatia · 14 Nov 2026
Olea Trail
2 races
· 25–45 km Show Hide
Croatia · 14 Nov 2026
Philippines · 14 Nov 2026
2/2 CP
Mt. APO Sky & Vertical Race
2 races
· 82–159 km Show Hide
Philippines · 14 Nov 2026
2/2 CP Turkey · 14–15 Nov 2026
ANTALYA CANYON ULTRA
6 races
· 8–70 km Show Hide
Turkey · 14–15 Nov 2026
Turkey · 14–15 Nov 2026
1/4 CP
Sagalassos Sky Ultra
4 races
· 5–42 km Show Hide
Turkey · 14–15 Nov 2026
1/4 CP Hungary · 14 Nov 2026
Tanuhegyek Trail
2 races
· 21–42 km Show Hide
Hungary · 14 Nov 2026
United Kingdom · 14 Nov 2026
Punk Panthers Wharfedale Skyline Half Marathon
Community
One recording helps every runner after you
Runners across the community use these simulators to plan their race day. Every prediction — how long the climbs really take, how much time slips away in aid stations, what the night miles cost — gets sharper with each real recording shared by someone who ran the course.
Share yours and you're improving the plan of every runner who toes that start line after you. It stays anonymous: verified against the course automatically, reviewed by a human, then folded into the shared calibration pool. It never appears publicly.
As a thank-you from us, every approved recording earns 3 months of TrailUP free.
How it works
- 1
Upload the recording of a race you ran
GPX or FIT, straight from your watch — we convert and trim it in your browser.
- 2
We verify it's really that course
Checkpoint by checkpoint, then a human review — only genuine recordings enter the pool.
- 3
The whole community's predictions improve
Stop timing and terrain get retuned from real races — and your 3-month code lands by email.
What you get
A race plan you can actually run off
Not a finish-time guess — a full checkpoint plan your crew can hold in their hands.
Your whole race, checkpoint by checkpoint
Clock arrival at every aid station — not just elapsed time. Each leg shows its distance, climb and descent, moving time and pace, so you know exactly what's between you and the next table of food.
- Cutoff margins on every gate — tight ones highlighted before they surprise you
- Edit stop time per station — 3 minutes at water points, 30 at your drop bag, and the whole plan recomputes
- Services at a glance — aid, crew access, pacers, drop bags and medics chip-tagged per checkpoint
See the course, not just the numbers
A live route map and elevation profile, hover-synced with the timetable — point anywhere on the course and see the kilometre, the altitude and the pace the model expects from you right there.
- Totals that tell the truth — moving time, station stops and en-route pauses split out, not hidden in one number
- Pin any checkpoint — arrival, stop budget, cutoff margin and services in one info bar
- Personal checkpoint notes — "poles out here", "extra water ×2" — carried onto your printed handout
A model tuned to you, not a formula
Two runners with the same target don't run the same race. Answer a handful of plain-language questions and the engine reshapes the whole plan around how you descend, fade and handle heat.
- Descending skill — runnable downhills and steep technical drops, tuned separately
- Late-race fatigue — auto-scaled by distance, with descents degrading faster than climbs, like real legs do
- Heat × your tolerance — race-day temperature costs daytime hours only, scaled by how you cope; nights slow you for darkness instead
- Altitude sensitivity — time spent high on the course costs what it should
Your local knowledge, on the plan
Every checkpoint takes a personal note — drop-bag contents, crew instructions, "poles out here" — and a 1–3 droplet water grade for the hot, exposed legs where one flask won't cut it.
- Everywhere you look — notes surface on the station bar, as icons in the timetable, and on page two of the printed handout
- Water droplets your crew understands — grade a checkpoint 1–3 and know exactly where to fill every bottle
- Private by design — notes stay on your device and never travel in shared links
Fuel every leg — the drop bags pack themselves
Pick real products — gels, bars, drink mixes — for each leg of the race, and every item automatically lands in the right bag: your start pouch, each drop bag, or a hand-off point where your crew meets you. Free with a TrailUP account.
- 288 real products from 37 brands — carbs, calories, sodium and caffeine per serving, read from each brand's official page
- A packing list per bag — "6× Gel 100, 1× Solid 160, 242 g carbs" for the start pouch, the same for every drop bag, ready to shop from
- Carbs per hour from your own plan — each leg's g/h uses the simulator's time for that leg, so a slower target quietly means more food in the bag
After the race · TrailUP athletes
Then find out what actually happened
The plan is half the story. Upload your recording afterwards and the analyzer lays your real race over it.
Every leg gets the verdict
Drop the GPX or FIT straight off your watch. The analyzer detects your passage through every checkpoint and lays your actual splits beside the plan — green where you banked time, red where it slipped away.
- Actual time and pace per leg — with the delta against your plan on every checkpoint
- DNF-aware — stopped early and it shows exactly how far you got, and what was left
- Compare against any plan — load a different saved simulation and the deltas recompute instantly
Real data: a Swiss Alps 100 finish, 42h31 analyzed against its 40h plan.
The debrief that makes the next one faster
A plain-language read of your day, written from the numbers: where the time actually went, how you faded, and what to set differently next time.
- Aid-station discipline — total stopped time vs plan, longest stop named and shamed
- Night legs and late-race fade — measured against what the plan already expected, not against zero
- Settings for next time — a fatigue-slider suggestion plus one-click "Re-simulate at your actual finish"
Share the plan
Every simulation lives in its link — send it to your crew, open it on any device, tweak and re-share.
Race-day handout
Print or PDF in a strict two-page format — timetable and profile on page one, your checkpoint notes on page two.
Saved simulations
Keep your A-goal, B-goal and cutoff-survival plans side by side and flip between them per race.
Plans
Free for everyone. More when you train with us.
The full pacing engine costs nothing and never will. Accounts add cross-device saves; the TrailUP app adds your real training data.
No account
- Full pacing engine on every catalog race
- Custom GPX planner for any route
- All athlete tuning — descents, fatigue, heat, altitude
- Share links & printable race handout
- Checkpoint notes & water flags (this device)
- 1 saved simulation (this device)
Free account
- Everything in the no-account tier
- Saves stored in your account — any device, any browser
- 1 saved simulation per race
- Race nutrition planner — leg-by-leg fueling + drop-bag packing lists
- Athlete profile — country, ITRA/UTMB index, units
- Redeem promo codes — 3 free months for sharing a race recording
Paid account
Most complete- Everything in the free account
- Unlimited saved simulations
- Post-race analysis — actual vs plan from your recorded GPX/FIT
- A training plan built for your race
- Watch sync — Suunto, COROS, Polar
Step 2
Don't see your race?
Tell us about it and we'll add it to the catalog. Mapping a course means checking the route, the aid stations and the cutoffs by hand — so we do it one race at a time, and yours moves up the queue when you attach a GPX.
- 1 Send the detailsName, distance, climb, country — a GPX if you have one.
- 2 We map the courseEvery aid station, cutoff and terrain factor checked against the organiser's own data.
- 3 You get an emailOnce when it's accepted, once more when the race page is live.
Already sent one? Check what's in the queue.
Two minutes, one form
Name, distance, country — and a GPX if you have one.
That's everything we need to start mapping. Attach the course GPX and your race jumps the queue — we'll email you when the page goes live.
Step 3 · Optional
Bring your own course
Not racing? Upload any GPX — a route you're scouting, a training loop, a race we haven't mapped yet — and get the same pacing model over it. No aid stations or cutoffs, but every kilometre is estimated the same way.