This climbing grade converter translates route grades between the YDS (American), French sport, UIAA and Font bouldering scales — using the consensus comparison table climbers actually travel with.
| Yosemite Decimal (YDS) | – |
| French sport | – |
| UIAA | – |
| Font bouldering (rough equiv.) | – |
| V-Scale (rough equiv.) | – |
Grades are opinions calibrated by consensus, not measurements — tables from different federations disagree by a half-grade at some boundaries, and local sandbagging is a proud tradition everywhere. Treat conversions as ±1 grade honest, especially bouldering↔route equivalences, which compare a few hard moves against sustained difficulty.
Nine Scales, One Argument
Every climbing region minted its own difficulty currency; converters are exchange bureaus with honest spreads. The table here follows the widely used federation consensus (the one printed in most guidebooks) — expect a half-grade of local variation as a feature, not a bug. Part of our Sports Calculators collection.
Anchor Conversions (Consensus Table)
- 5.10a ≈ French 5c ≈ UIAA VI− — the grade where letter grades begin and casual climbing ends
- 5.11d ≈ 7a — the famous redpoint milestone (the “7a” of European sport climbing)
- 5.12a ≈ 7a+, 5.13a ≈ 7c+, 5.14a ≈ 8b+ — the elite staircase, each step historically a generation’s project
- Bouldering bridge: a V5 boulder problem’s hardest moves ≈ a 5.12a route’s crux — sustained vs peak difficulty keeps the equivalence permanently approximate
Grade Culture Notes
- YDS letters (a–d) subdivide 5.10 and above; below that, +/- appears regionally.
- French grades use + for half-steps (6a+); UIAA mixes numerals with +/−; the Ewbank (Australia) and British (E-grade + tech) systems sit outside this table entirely.
- Trad grades add danger ratings (PG/R/X in the US) — difficulty conversions say nothing about consequence.
- The only conversion that matters at the crag: the first ascensionist’s mood. Sandbag awareness is a survival skill.
Related Tools
- Vertical Jump Calculator — dyno math for the boulderers
- Sports Calculators — the full collection
Frequently Asked Questions
What is 5.10a in French grades?
About 5c (UIAA VI−) in the consensus table this converter uses. The 5.10s run: a = 5c, b = 6a, c = 6a+, d = 6b. Expect ± a half-grade between guidebooks — grading is calibrated opinion anchored by first-ascent and repeat consensus, not instrumentation.
What YDS grade is 7a?
≈ 5.11d. The 7a milestone anchors the scales’ middle: 6a ≈ 5.10b, 6b+ ≈ 5.11a, 7a+ ≈ 5.12a, 7c ≈ 5.12d, 8a ≈ 5.13b. This is the band where most traveling sport climbers live, so the conversions here get the heaviest real-world use.
How do bouldering grades convert to route grades?
Roughly: V0 ≈ 5.10a crux moves, V3 ≈ 5.11a, V5 ≈ 5.12a, V8 ≈ 5.13a — equating the hardest few moves of a boulder problem to a route’s crux. Endurance isn’t priced: a V5 climber may still pump off a 5.11 route, and route climbers fail V5s their fingers can’t hold. The table prints these as “rough equiv.” for that reason.
Why do grades differ between gyms and areas?
Because graders are human and rock varies: friction, hold style, route length, and local tradition all bend numbers. Historic areas (and old-school first ascensionists) grade stiffly — “sandbagged” — while commercial gyms grade generously. Convert with the table, then calibrate against a known benchmark climb on day one anywhere new.
What do the letters after 5.10 mean?
YDS subdivides 5.10–5.15 into a/b/c/d quarter-steps as difficulty outgrew whole numbers in the 1970s. French uses + (6a, 6a+, 6b), UIAA uses +/− on Roman numerals. All are attempts to slice a continuous difficulty spectrum into nameable bands — the boundaries are social, the spectrum is real.
Is this climbing grade converter free?
Yes — free, instant, no sign-up. Climb safely — check your knots, not just your grades.