Keyboard Controls for Browser Games

There is no standard for browser game controls, but there are strong conventions, and a game that follows them needs almost no explanation. Here is what they are and why they exist.

The conventions

Every game on this site accepts both arrow keys and WASD, so you never have to find out which one it wanted. That costs a few lines of code and removes a whole category of small frustration.

Why both schemes exist

Arrow keys are self-documenting - the labels tell you what they do - which makes them right for a game a stranger might play once. WASD leaves the right hand free for a mouse and puts movement under the left hand's resting position, which matters when a game needs several keys at once.

For a browser arcade game, neither is clearly better, which is why supporting both is the sensible answer rather than a compromise.

Ghosting: the quirk that eats your inputs

Many keyboards - particularly inexpensive membrane ones - cannot report every combination of simultaneous key presses. The keys are wired in a grid, and certain combinations become ambiguous, so the keyboard reports fewer keys than you are actually holding. This is called ghosting or blocking.

In practice it shows up as a jump that does not register while you are holding a direction, usually in one direction only. If you find that holding right and pressing jump works but holding left and pressing jump does not, that is your keyboard rather than the game.

The workaround is to use the other movement scheme - if arrows are ghosting, try WASD, or the reverse. Different physical keys sit in different grid positions, and the conflict usually disappears.

Games should not hijack your typing

A game that listens for keys globally will respond while you are typing in a search box, which is maddening. The fix is straightforward: before acting on a key, check whether the event came from a text input, a textarea, a select or an editable element, and ignore it if so.

Every game here does that check, which is why you can use the site search on a game page without the cat leaping about.

Preventing page scroll

Space and the arrow keys scroll the page by default. In a game that uses Space to jump, this means every jump also scrolls the page, which is unusable.

Games must suppress that default behaviour while playing - and only while playing, so that the page still scrolls normally when you are reading the article below the game. This is a small detail that is very obvious when it is missing.

Held versus pressed

Two different questions get confused constantly, including by experienced developers.

• Held: is this key down right now? Correct for continuous movement.
• Pressed this frame: did this key go down since the last update? Correct for discrete actions such as jumping.

Using held state for a jump produces a cat that jumps repeatedly while the key is down. Using pressed state for movement produces a cat that moves one pixel per press. Both are immediately recognisable once you know to look for them.

Key Takeaways

• Arrow keys and WASD are both conventions; a good game accepts both so the player never has to guess.
• Space is the near-universal primary action, with P or Escape for pause and R for restart.
• Keyboard ghosting can silently drop simultaneous presses - switching between arrows and WASD usually fixes it.
• Games must ignore keys that came from text fields, or they hijack your typing.
• Held state and pressed-this-frame state are different questions, and confusing them produces obvious bugs.

Frequently Asked Questions

Why does my jump sometimes not register?

Often keyboard ghosting - some keyboards cannot report certain simultaneous combinations. Try the other movement scheme.

Can I remap the keys?

Not on this site. Both common schemes are accepted on every game, which covers the usual preferences without a settings screen.

Why does the page scroll when I press Space?

That is the browser's default. A game should suppress it while playing; if one here does not, please report it.

Is a mechanical keyboard better for games?

For simultaneous key presses, often yes, because they more commonly support reporting many keys at once. For a two-key arcade game it makes little difference.

Do these games support a gamepad?

Not currently. Keyboard, mouse and touch are supported everywhere on the site.