Discovery
- 15 to 30 km
- ≈ 300 to 800 m D+
- ≈ 2 to 5 h
Managing your own pace and fuelling over a single day.
No dedicated guide yetChoose your format
Which trail race distance fits your level.
Discovery, 50K, an 80–100K ultra, 100 miles or a multi-day trek: these are not steps of the same ladder. This tool helps you choose the one that matches your current situation, not your stated ambition.
Edition 1.0 · August 2026Find your format
Which trail format fits you today?
Answer four simple questions: the line below places the format that best matches your current situation, not your long-term ambition.
These answers only power this calculation shown in your browser. They are not sent, stored or linked to an account.
Discovery (15–30 km)
50K trail
80–100K ultra
100 miles / 160K+
Multi-day trek
Format that fits you today
50K trail
A full day of effort, without a night or extended self-sufficiency to manage.
Read the matching guideOverview
Five formats, five different dominant demands.
These numbers are orders of magnitude, not individual predictions — always read the real course on its own terms.
50K trail
- ≈ 50 km
- ≈ 1,500 to 3,000 m D+
- ≈ 6 to 10 h
Long endurance and repeated downhill management.
Read the guide80–100K ultra
- 80 to 100 km
- ≈ 3,000 to 6,000 m D+
- ≈ 14 to 24 h
Prolonged nutrition and one night to cross.
Read the guide100 miles / 160K+
- 160 km and beyond
- ≈ 6,000 to 10,000 m D+
- ≈ 28 to 45 h
Sleep, crew logistics and decisions under extreme fatigue.
Read the guideMulti-day trek
- Varies by stage plan
- Varies by mountain range
- Several days of walking
Stage logistics, accommodation and self-sufficiency — no clock.
Read the guideAvoiding the number trap
Reading these benchmarks without chasing a distance.
The format “above” is not automatically the right goal. The useful question is: does this format fit your current load, your preparation time and the life you have around the race?
A marker, not a grade
These categories help choose a fitting preparation; they do not measure your worth or seriousness as a runner.
Progression is not mandatory
Staying on the same format for years, or returning to it after an ultra, is a perfectly coherent choice.
Trekking is not a tier
It does not compare to race formats on this scale: it is a different way to use a route, not a step to complete before or after an ultra.
Format does not replace the real course
Two races of the same format can demand very different things depending on elevation, altitude or climate — always check the specific course you are targeting.
The right format is the one you can seriously prepare for with the time, energy and life you actually have — not the one that sounds most impressive.
Across several seasons
Progressing without skipping a step out of overconfidence.
A realistic progression leaves time to absorb each format before changing scale — research validates no universal calendar, but one principle stays constant: a new load needs time to become a mastered load.
- 01
Finish comfortably
Before changing format, finish the current one without extreme exhaustion or a lingering injury.
- 02
Repeat before increasing
Several successful races at the same format give a more reliable base than one isolated result.
- 03
Change one variable at a time
Increase distance, elevation or duration — avoid stacking several jumps (distance and technicality and altitude) on the same race.
- 04
Choose trekking on its own terms
This choice does not depend on your previous race format: it answers a different desire, at any point in your journey.
These markers help frame a decision; they do not replace individual advice when pain, persistent fatigue or a serious doubt shows up.
FAQ
FAQ
Do I have to start with a small format?
No. The tool starts from your current situation (volume, longest run, goal), not a universal progression rule. Someone already active in another endurance sport can legitimately aim further from the start.
Does this test replace advice from a coach or doctor?
No. It is a general orientation tool, not an individual assessment. Pain, persistent fatigue or a specific health condition call for tailored advice, regardless of the result shown here.
Can I choose trekking without ever having run a trail race?
Yes. Trekking does not require race experience: it requires walking, stage logistics and self-sufficiency — a different profile, not a higher tier.
The recommended format does not match my goal, what should I do?
It is an invitation to look at why: often a still-modest volume or longest run explains the gap. Nothing stops you from aiming for that format later, once that base is built.
Method
Evidence behind this guide
Sources support general principles on load and progression. They do not define a universal individual threshold between two formats.
- Soligard et al. / IOC (2016)ConsensusHow Much Is Too Much? IOC Consensus Statement on Load in Sport and Risk of Injury. Br J Sports Med. doi:10.1136/bjsports-2016-096581.
Consensus on load-recovery balance and injury risk when progression between formats happens too quickly.
↗ - Berger et al. (2024)Scientific reviewLimits of Ultra: Towards an Interdisciplinary Understanding of Ultra-Endurance Running Performance. Sports Med. doi:10.1007/s40279-023-01936-8.
Interdisciplinary framework for the physiological and logistical limits of ultra-endurance, useful for understanding where load becomes qualitatively different.
↗ - Scheer & Krabak (2021)Scientific reviewMusculoskeletal Injuries in Ultra-Endurance Running: A Scoping Review. Front Physiol. doi:10.3389/fphys.2021.664071.
Maps musculoskeletal injuries reported in ultra-endurance, relevant when skipping a step out of overconfidence.
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