Nail spacing is the single most discussed specification on any sadhu board. It is also the most misunderstood. The number on the label, whether 8, 10 or 20 millimetres, is the distance between the centres of two neighbouring nails. The smaller the number, the more nails per square centimetre, and the more the load on your foot gets distributed across many points. The larger the number, the fewer nails, and the more concentrated the pressure on each one.
This is why a 20mm board feels dramatically different from an 8mm board even when both use the same nail length and the same wood. It is not about a tougher or softer practice. It is a different geometry of contact between you and the board.
What 8mm Spacing Actually Feels Like
An 8mm board is what most newcomers begin on, and for good reason. The nails sit close enough together that your weight is shared across hundreds of contact points. The first sensation is sharp, but it diffuses quickly into something more like a strong tingling pressure. Most first-timers can stand for thirty to ninety seconds on 8mm without panic, then build from there.
In our Kostopil workshop, 8mm is the spacing we recommend for anyone new to nail standing, for office workers whose feet have not touched raw ground in years, and for studios introducing the practice to mixed-experience groups.
10mm Spacing: The Working Middle
10mm is the workhorse. It is the spacing many long-term practitioners settle into for daily sessions because it offers a noticeable challenge without becoming a stunt. The difference between 8mm and 10mm is not huge on paper, but the practice changes. You feel each nail more distinctly. Breath becomes more important. Subtle shifts in weight, the kind you can fudge on 8mm, become impossible to hide.
If you already practice yoga, qigong or any standing meditation, 10mm tends to integrate well after a few weeks on 8mm. It is also the spacing where most people stop feeling that the board is doing something to them and start feeling that they are doing something with the board.
20mm: A Serious Practice
20mm is not for showing off and it is not for absolute beginners. With twice the spacing of 10mm, each nail carries roughly four times the load when you stand evenly. The sensation is sharper, more concentrated, and far less forgiving. Step on a 20mm board cold, without preparation, and your nervous system will tell you immediately.
Eugene Oliynyk, who founded METADESK, has practiced daily since 2018 on every level including 20mm. He is direct about it: 20mm is not a graduation prize. It is a specific tool for specific work. People who use 20mm well usually came to it slowly, after one or two years on tighter spacings, and they often return to 10mm for regular sessions and reserve 20mm for shorter, more deliberate ones.
A Realistic Progression
If you are choosing your first board today, start with 8mm. Practice on it for at least four to six weeks before considering anything else. The goal in that period is not duration, it is quality. You want to learn how to stand without bracing, breathe without holding, and step off without flinching.
From there, 10mm is the natural next step, and many practitioners never feel the need to go further. There is no shame in that. The depth available on a 10mm board is more than enough for a lifetime of practice.
20mm is worth considering only if you have a clear reason, such as preparing for longer standing meditations, working on a very specific quality of attention, or because your teacher recommends it.
What the Spec Sheet Does Not Tell You
Two boards with identical 10mm spacing can still feel different. Nail length, nail material, the species and dryness of the wood, the finish on the foot side, the overall board dimensions, and even the weight of the board all change the practice. A heavier board sits more firmly under your feet, which means less micro-movement and a steadier sensation.
If you are unsure which spacing is right for you, our balance boards collection shows the full range with notes on intended use. The full METADESK catalogue lists every active board and pattern.
One Honest Recommendation
Pick the spacing your current practice can support, not the one that sounds impressive. The board you actually stand on every morning is infinitely more useful than the one you bought because it looked serious. Most people are best served by 8mm for the first season and 10mm thereafter. 20mm is a tool, not a target.