Climbing Tools
Climbing tools built on the actual physics — why 120 degrees is the critical anchor angle, why a short fall near the belay hits as hard as a huge one high up, and grade conversion across the Yosemite, French, UIAA, V and Fontainebleau scales.
Twelve climbing knots with steps — and, for each one, the specific way it fails.
Crevasse Rescue & Glacier Travel CalculatorRope spacing for a glacier team, and what a Z-drag actually delivers once friction has taken its share — which is far less than 3 to 1.
Climbing Pyramid & Send LogLog sends and attempts, and see the difference between your hardest send and the grade you actually climb.
Sport Route Gear & Rope Length EstimatorHow many quickdraws a route needs, and whether your rope is genuinely long enough to lower from the anchor — the check people skip.
Hangboard Training TimerRepeaters, max hangs, min-edge and density protocols with audio cues and added-weight percentages — plus who should not be using one yet.
Trad Rack BuilderWhich cam fits a given crack, how well it will sit, and the whole Camalot range drawn to scale for comparison.
Belay Device & Rope Diameter CheckerWhich belay devices accept your rope diameter, which have it in their optimal band, and which are outside their rated range entirely.
Rope Retirement CheckerWhether your rope is still in service life — inspection checklist first, then age and usage arithmetic, because inspection is what actually decides it.
Anchor Angle Force Multiplier CalculatorWhy 120 degrees is the critical angle — the force on each anchor leg, drawn to scale as you change it.
Fall Factor & Impact Force CalculatorWhy a short fall near the belay hits as hard as a huge one high up — fall factor, peak force, and what the rope is actually doing.
Climbing Grade ConverterYDS, French and UIAA for routes; V-scale and Font for boulders — type any grade in any scale, with the caveat that conversions are approximate.
About these climbing tools
The most counterintuitive number in climbing is the fall factor, and it explains why a short fall can be more violent than a long one. Fall factor is the distance fallen divided by the length of rope paid out to absorb it, and it tops out at 2. Fall ten metres on fifty metres of rope and the factor is 0.2 — the rope has plenty of length over which to stretch and the force stays modest. Fall two metres onto one metre of rope, straight onto the belay, and the factor is 2, with the same rope having a fraction as much material to absorb the same energy per metre fallen. The force on the anchor is far higher despite the fall being a fifth as long. This is why the first piece of protection off a belay matters more than any piece above it, and why the start of a pitch is its most dangerous part. The second thing worth understanding is that grades are consensus rather than measurement. No instrument reads back 5.11a; the number is what a community of climbers has settled on by comparison, and it drifts with era, region and rock type. Conversion tables between systems are approximations of approximations, and being a grade out is normal rather than an error. The third is that anchor forces multiply rather than divide as the angle between legs opens up. Two legs at 60 degrees each carry about 58 per cent of the load, which is a real saving. At 120 degrees each carries the FULL load, so the anchor is no stronger than one piece. Past 120 degrees each leg carries more than the load it is supposedly sharing, and the arrangement is actively worse than a single placement would have been.