Most standard arcade buttons are 30mm for main action buttons and 24mm for utility buttons like Start and Coin.
If you’re building a fight stick or restoring a cabinet, the size that matters is the mounting hole diameter, not the cap you see on top. These two sizes cover the vast majority of Japanese-style panels, with 28mm appearing on some American-style parts. Before ordering anything, measure the cutout in your panel — that single number decides which buttons you can buy.
What Does “Standard Arcade Button Size” Actually Refer To?
The number in a button’s name refers to the panel cutout it fits into, not the visible cap face. This is the most common point of confusion for first-time builders. A button labeled 30mm will sit in a 30mm hole, and its cap will measure slightly larger so it doesn’t fall through.
Buying by visual similarity instead of exact diameter leads to frustration. The dimensions are not interchangeable.
24mm vs 30mm: Which Size Goes Where?
On a typical Japanese-style fight stick, the six or eight main gameplay buttons are 30mm, while the Start, Select, Coin, and Home buttons are 24mm. That split exists because action buttons need a larger target for rapid pressing, while utility buttons are tapped occasionally and can sit closer together.
Compact and leverless layouts sometimes use 24mm more broadly across the whole panel. Some American Happ-style parts use a 28mm mounting hole with a larger 32mm cap, so a “standard” button from one region is not guaranteed to match another.
Sanwa’s well-known OBSF series follows this pattern directly.
What To Check Before You Order Replacement Buttons
Measure the mounting hole first. A digital caliper gives the most accurate reading, but a ruler works fine for a whole-number diameter. Write it down, then match your order to that number exactly.
- Mounting depth:
- Wiring type:
- Clearance behind the panel: Confirm there is room for the button body and attached wires before you commit to a part.
If you are comparing brands and builds side by side, our roundup of tested arcade game buttons for custom panels covers what holds up under heavy play.
| Button Size | Typical Use | Notes |
|---|---|---|
| 24mm | Start, Select, Coin, menu buttons | Common on Japanese-style panels; compact for tight rows |
| 28mm | Some American and Japanese parts | Happ-style examples use a 28mm hole with a 32mm cap |
| 30mm | Main action buttons on fight sticks | The standard for gameplay buttons; needs a 30mm hole |
FAQs
Can I use a 30mm button where a 24mm hole is drilled?
No. The 30mm button requires a 30mm cutout to sit flush and lock in place. Fitting it into a 24mm hole would require widening the panel, which is rarely practical without damaging the artwork or the wood itself.
Do Sanwa buttons fit American-style arcade panels?
Not always. Sanwa OBSF buttons use a 30mm or 24mm mounting hole with plastic side clips, while some American Happ-style parts use a 28mm hole with a different locking mechanism. Check the cutout diameter and mounting depth before assuming compatibility.
Are all 30mm arcade buttons the same size?
The mounting hole is 30mm across brands, but the cap diameter and overall body depth can vary.
References & Sources
- Focus Attack. “24mm vs 30mm: Choosing the Right Japanese Arcade Button.” Explains the difference between 24mm and 30mm mounting holes for Japanese-style buttons.