BlackJack 21

Two players, one keyboard, and a very small screen between you. That is one classic shape of browser multiplayer. Another is a quick online match against whoever happens to be around. Either way, a session is a run of short rounds where the result depends on another person's decisions as much as yours. Trash talk is optional but common, and so is the rematch.

• Tap, hold and swipe on phones and tablets
• Mouse or trackpad on a computer; arrow keys or WASD where the game asks for movement
• Press Escape or the exit button to leave the full-screen player

1. 1Pick a mode from the menu. If playing locally, note which keys belong to each player.
2. 2Start a round and spend the first few seconds getting a feel for your character; your opponent is doing the same.
3. 3Focus on your opponent's position and habits rather than your own, especially in fighting or racing games.
4. 4Play a best-of-three or five. A single round rarely settles anything.

• Free to play, nothing to install, no account needed
• Loads in the browser tab and opens full screen when you press Play
• Plays best with the phone turned sideways or on a wider screen
• Touch controls on phones and tablets, mouse and keyboard on a computer
• Listed under Multiplayer

BlackJack 21 turns a laptop or tablet into a two-person arcade with no setup. It is free, needs no download or login, and rounds are short. The unpredictability of a human opponent keeps even simple games interesting far longer than they would be alone.

Suits pairs and small groups, from children playing with a sibling to adults at a kitchen table. Solo players who want online opponents also fit. It works best on a laptop or tablet.

Can I play BlackJack 21 alone?

Many multiplayer games include a single-player or computer opponent mode. Check the start screen. Online modes also work solo by matching you with others.

Which keys does each player use?

Shared-keyboard games usually give WASD to one player and arrow keys to the other, with extra keys for actions. The game shows this before the match.

Is online play safe for children?

Games on this site have no accounts or chat, so interaction is limited to the game itself. A parent should still be aware of what their child is playing.