# The ruler > Thin, snappy and found on every office desk. Why a ruler stings out of proportion to its weight, why the edges are the problem, and what to check before use. - Canonical URL: https://consensualspanking.co.uk/implements/ruler/ - Section: Implements - Updated: November 2026 (2026-11-01) - Audience: consenting adults over 18 only. Everything on this site concerns consenting adults over 18. A ruler is a light implement with a formal air, and the formality is doing most of the work. What it actually delivers is a shallow sting. What it can do wrong is entirely about the two square edges running down its length. --- ## In short - A ruler is almost pure surface sting. Very little of the force reaches the muscle. - The long edges are the hazard. Landed flat it is mild; landed edge-on it is a chisel and will break skin. - Never use a metal ruler or one with a metal edging strip. That is the single clearest do-not on this page. - Thin wood and plastic snap. A snapped ruler leaves a splintered end or a sharp shard travelling at speed. Before anything else: everything on this page is about consenting adults over 18. The ruler in question is the plain one from a desk drawer, and when it turns up in roleplay the setting is an office or a formal appointment, which is where its particular atmosphere comes from. ## What it is A flat strip of beech or another light hardwood, usually 30 centimetres long, three or four centimetres wide and three or four millimetres thick, with square edges and a printed scale. Heavier hardwood versions and machined perspex ones exist. Metal ones exist too and have no place here. Thin, rigid, light, and flat. That combination means it moves very fast for very little effort, which is the source of both its sting and its problems. ## What it feels like A quick flat clap with a sharp edge to the sensation, landing as a narrow band rather than a patch, and fading fast. There is nothing behind it, so it does not push into anything, and it is one of the few implements you can use at a genuinely brisk pace without accumulating much depth. Its nearest relative is the [wooden spoon](https://consensualspanking.co.uk/implements/wooden-spoon/), which has similar snap but a much smaller and rounder contact area. Against a [crop](https://consensualspanking.co.uk/implements/crop/) it is broader and duller, and against a [cane](https://consensualspanking.co.uk/implements/cane/) it is a completely different order of thing, sharing only the fact that both leave lines rather than patches. What a ruler is really good for is a fast, light, noisy sequence over a small area, and for the specific atmosphere it carries. If the object matters more to you than the sensation, that is a legitimate reason to choose it, and a good argument for keeping the force low and letting the object do the work. ## How it fails Everything on this list comes back to the edges. A ruler has two long square corners running its whole length, and they are typically machined rather than rounded. Landed flat, the face spreads what little force there is across a band. Landed at an angle, the corner arrives first and concentrates all of it into a strip a millimetre or two wide. That is a chisel, and it breaks skin. This is not a theoretical risk, it is the ordinary consequence of an implement that is easy to rotate in the hand. Metal is the second failure and the reason for the flat prohibition above. Metal rulers and metal edging strips have real edges, they do not flex, and they cut. Nothing about the appeal of a ruler requires metal and there is no version of this that is worth trying. The full list is on [things never to use as an implement](https://consensualspanking.co.uk/implements/never-use/). Snapping is the third. Rulers are made to sit in a desk drawer, not to be swung a hundred times, and thin softwood or brittle plastic gives way eventually. A broken plastic ruler produces a shard with a genuinely sharp point on it, which is the reason I would use a wooden one or nothing. > **Two minutes with sandpaper.** Round off both long edges and both ends with fine sandpaper before you use a ruler for this. It takes almost no time, it does not affect how it feels when it lands flat, and it removes most of what makes an angled stroke dangerous. Of all the small modifications in this section this is the one with the best return. ## Technique Hold it near one end with a firm grip so it cannot rotate. Loose fingers are how an edge ends up leading. Wrist only, short strokes, and the face arriving parallel to the skin. Aim at the fullest part of the lower buttock, well away from the hip and the crease. Because a ruler is short you have to be close, which is actually helpful, since there is very little tip travel to worry about and almost no wrap. Keep the force low deliberately. Hitting hard with a thin rigid object is how you get an angled stroke, a snapped ruler or a welt with a defined edge, and a ruler used hard is not more impressive, it just stops being the light snappy thing that made it worth picking up. Move around. The contact band is narrow, so strokes stack fast, and ten in one place is a different proposition from ten spread out. Warm up with a hand first, because cold skin plus a rigid edge is where splits happen. See [warm-up](https://consensualspanking.co.uk/guide/warm-up/). ## How it marks Thin bands of redness that usually clear within a few hours, sometimes with a faint line at each boundary. Bruising is uncommon from flat strikes and tends to be light when it happens. Edge strikes are the exception and look quite different: a narrow raised welt with a sharp outline, slow to settle, and the one that can break the surface. If you are seeing those, the technique is wrong or the edges need sanding. Broken skin is the point at which the legal position stops being academic. Under *R v Brown* [1993] UKHL 19, consent is not a defence to actual bodily harm in England and Wales, and ordinary redness sits well below that line while a wound does not. See [marks and bruising](https://consensualspanking.co.uk/guide/marks-and-bruising/). ## Buying and improvising This is the cheapest object in the section. A plain beech ruler from a stationer costs somewhere between one and three pounds and there is nothing wrong with it. Heavier hardwood versions sold for the purpose exist and cost more, and the main thing you get for the money is properly rounded edges and a better finish, which is worth something. What to look for: solid hardwood, no metal anywhere, no printed lacquer that can lift, and thickness rather than length. What to avoid: metal, metal-edged, plastic, anything folding or hinged, and perspex with machined square edges. Honestly, if what you want is sting with an office flavour and you are willing to spend more than five pounds, a light [strap](https://consensualspanking.co.uk/implements/strap/) does it better, more safely and for longer. The ruler earns its place through what it looks like rather than what it does. ## Care Almost none required. Keep it dry, keep it out of the sun, and look down its length occasionally for cracks running with the grain, especially near the middle where it flexes most. Replace it when you find one, which will cost you a couple of pounds. Wooden objects are porous, so a ruler used on bare skin should be washed and dried like anything else that touches a person, and kept to one partner unless it is cleaned properly in between. ## Read next - [Where it is safe to strike](https://consensualspanking.co.uk/guide/where-it-is-safe-to-strike/) - [Improvised implements](https://consensualspanking.co.uk/implements/improvised/) - [The wooden spoon](https://consensualspanking.co.uk/implements/wooden-spoon/) - [All implements](https://consensualspanking.co.uk/implements/) ## Sources 1. *R v Brown* [1993] UKHL 19, House of Lords. [bailii.org](https://www.bailii.org/uk/cases/UKHL/1993/19.html) > **Not legal advice.** Where this page mentions the law, it is general information written from an England and Wales position unless it says otherwise, and it is not legal advice. Scotland and Northern Ireland have their own law. If your own legal position matters, speak to a solicitor. ## Common questions ### Does a ruler hurt to be spanked with? It stings sharply and shallowly. A thin flat piece of wood arrives fast and lands as a narrow band, so almost all of the sensation stays at the surface and very little reaches the muscle. It is one of the lighter implements in terms of what it does, and one of the sharper ones in terms of how it feels. ### Is it safe to use a ruler for spanking? Only if it lands flat and only if it has no metal on it. A wooden ruler striking with its face is mild. The same ruler landing on its long edge concentrates everything into a square-cornered strip a millimetre or two wide, which will split skin. Never use a metal ruler or a ruler with a metal edge strip. ### Why do rulers snap? Because they are thin, they are not designed to take repeated impact, and cheap ones are made of soft wood or brittle plastic. A snapped wooden ruler leaves a splintered end, and a snapped plastic one leaves a sharp shard. Check for cracks along the grain before use and replace it at the first sign of one.