Terms and conditions
The deal, in plain language
Using eveneffort means accepting what follows. It is short, because the service is simple: we do some physiology maths, you decide how to run your race.
Last updated 3 August 2026
What the service is
eveneffort is a free calculator that redistributes a goal finish time across a marathon course according to its elevation profile and, where a forecast is available, the expected race-day weather. There is no account to create and nothing to subscribe to. We may change, add or remove features — including courses — at any time, and we may take the site down without notice.
Pacing advice, not medical advice
This is the part worth reading properly. The splits we produce are a mathematical model’s estimate, not a training prescription and not medical advice. They assume the goal time you gave us is one you are actually fit to run; the model has no way to know otherwise, and it will happily build you a beautiful plan for a time beyond your current fitness. Fueling cues are generic guidance based on a carbohydrate target you set, not a nutrition plan for your body.
Running a marathon carries real risk of injury and, in rare cases, worse. You are responsible for your own training, pacing and safety on the day, and for deciding to slow down or stop regardless of what any band on your wrist says. Consult a doctor before starting endurance training, and follow the instructions of race officials and medical staff over ours. Conditions on the day — heat, wind, a course change, how you slept — will always outrank a plan made in advance.
Accuracy
We build each course from published elevation data and we work hard to get it right, but course routes change between editions, GPS elevation carries error, and weather forecasts are forecasts. The underlying energy-cost model is drawn from published research (see our methodology) and is a well-supported approximation of how gradient affects running economy — not a law of nature, and not tuned to you personally. We do not warrant that any split, adjusted finish time or forecast is accurate, and you should treat all of it as a starting point for your own judgement.
Printed bands
You can print a paceband yourself for free, forever. We also sell a physical one for $9.99, made by hand and posted to you. Payment is handled by Stripe, and placing an order means accepting our shipping & refunds terms, which set out delivery times and how refunds work. Please check your goal time and course before ordering — each band is printed for one specific plan.
Acceptable use
Use the site for planning your own races. Don’t attempt to disrupt it, scrape it at volume, or hammer the forecast endpoint — it sits on a rate-limited third-party API and abusing it degrades the site for other runners. Don’t resell the pacing output as your own product.
Ownership
The site, its design, its written content and our course data compilation belong to us. The pace chart you generate is yours — print it, share it, wear it, no permission needed. The underlying research we build on belongs to its authors and is cited on the methodology page. Race names and trademarks belong to their respective organisers; we are not affiliated with, endorsed by, or sponsored by any marathon or race organisation.
Liability
The service is provided “as is”, without warranties of any kind, to the fullest extent the law allows. We are not liable for injury, a missed goal time, a bad race, or any indirect or consequential loss arising from using the site or a band. Where liability cannot be excluded, it is limited to what you actually paid us — which for most people is nothing. Some jurisdictions don’t allow these exclusions, in which case they apply only as far as they legally can, and nothing here removes your statutory consumer rights.
Governing law and changes
These terms are governed by the laws of the United States. If they change we will update the date at the top of this page, and continuing to use the site means accepting the revised version. Questions go to morenog150@gmail.com. See also our privacy policy.