V2 went quick. V3 took a season. V4 has taken a year so far and shows no sign of finishing. The usual explanations are that you aren't trying hard enough, or your footwork is holding you back, and either could be true. Here's a third reading. It's a hypothesis, and it comes out of our own calculator.
The calculator on our finger strength and climbing grades post takes your one-arm lift on a 20mm edge, divides it by your bodyweight, and hands back a grade band. That post argues finger strength is a ceiling, not a grade, and we stand by it. What we hadn't done until now was visualize every grade by finger strength and look at the shape.
Why does V4 take a year when V3 took a season? Could the grade itself be wider?
Grades by finger strength, visualized
The thresholds were measured from real climbers, a dataset of over 100. Each lifted one-handed from a 20mm edge and shared their hardest grade sent outside in the past six months. That's our chart, not a published norm, and we're not going to dress it up as one. What's worth your attention is the shape.
Look at the widths. V4 runs from 36% to 59% of bodyweight, 23 points. V7 runs 63% to 81%, 18. V12 and V13 take 15 points each. Between those sit pairs so narrow they almost touch: V2 and V3 at 4 points and 3, V5 and V6 at 2 and 2, V10 and V11 at 4 and 4. Above V14 the band is open.1
Warm up first and stop on pain. Full safety guidance.
The hypothesis
A climber moves up through the grades and hits a wall. The theory is that the wall is a grade that asks for more than the one before it. Some grades feel similar to each other, which is why people give slash grades like V5/6, and on the chart those grades sit close together: V5 and V6 together occupy 4 points. V4 alone takes 23.
Wide band
A grade that asks more than the previous one: fingers, body size, tension, skill, climbing IQ. The chart can only see fingers. Finger strength is the one requirement we can put a number on, so it's the one we're reading the shape from.
That last point carries the whole argument, so it's worth being blunt about. Asking more means all of it: fingers, body size, tension, skill, climbing IQ. The chart measures fingers and nothing else. If a grade's finger band is wide, that could be the one visible edge of a grade that's wide in all of it. Or it could be a quirk of where the thresholds fell. We can't tell from the chart alone, which is why this is a hypothesis and not a finding.
What the widths would cost
Run the arithmetic against what we already know about how fingers adapt. Our timelines post puts finger strength gains at roughly 5 to 10% over an 8 to 12 week cycle, with the fast neural gains arriving first and the slow tissue gains after. A 23-point band at that rate isn't one block. It's several, and the back half of a wide band comes slower than the front. Two seasons at V4 stops looking like a personal failure and starts looking like the price of the rung.
The narrow bands cut the other way. Our testing post puts test-retest variation on this lift at 6 to 8%, which is wider than the whole of V5 or V6. The calculator can't tell a V5 lift from a V6 lift, and on a given day neither can you. If those two grades have always felt like one grade to you, the chart agrees.
Mine was V8. It felt like a tough one to get past, and when I drew this chart I wanted it to explain why. It half does. V8 runs 81% to 91%, 10 points, five times the width of V5 or V6. It isn't the widest rung, though; V4 and V7 are both wider. So my one data point fits the hypothesis partly, which is about what one data point should be allowed to do.
Where the hypothesis stops
Finger strength on a 22mm edge correlated very strongly with bouldering grade (r = 0.89) in 19 male climbers, 6b+ to 8c (V4 to V15).
So the number is worth taking seriously. What it can't show, in 19 men measured once, is that raising the number moves the grade, or what the chart looks like for women or above 8c.
Finger strength tracks grade. That part isn't the hypothesis; it's the best-supported relationship in the sport's testing literature, and a 2025 review of 74 studies found that climbing-specific tests separate ability levels where general fitness tests don't. What that literature can't do is turn a correlation measured once into a rule about walls. 19 men, tested one time, is a snapshot. Our dataset is bigger, but it's the same kind of snapshot: it says where climbers at each grade tend to sit, and nothing about how anyone got there.
So the honest version is this. The bands are real numbers from real climbers. The reading of those bands as walls is ours, it's new, and it could be wrong. That's what a hypothesis is for.
What to do with it
If you're stalled and your number sits inside one of the wide bands, treat the wall as a wide one. Test at the start and end of a block, not every week, on the same 20mm edge with the same grip. Write the lift, the edge, the grip and the date down. Expect this rung to take longer than the last one did, and don't read a flat month as a verdict.
If your number sits at the top of your grade's band and the next grade still isn't coming, the chart can't see what's missing. That's an answer on its own. Body size, tension, skill, climbing IQ: whatever the wide band is asking for, it isn't more fingers, and another hangboard block won't be the thing that moves you.
Retest in 8 to 12 weeks on the same edge. If the number moved and the grade didn't, you've learned which requirement wasn't fingers.
1 Above V14 it's an open band because even the grading of V15 to V17 is known to be a weird zone right now.
Sources
- Buraas, B.F., Brobakken, M.F., & Wang, E. (2025). Climbing performance in males: the importance of climbing-specific finger strength. European Journal of Applied Physiology.
- Faggian, S., et al. (2025). Sport climbing performance determinants and functional testing methods: A systematic review. Journal of Sport and Health Science.