The best .io games are Agar.io, Slither.io, Diep.io, Krunker.io, Skribbl.io, Paper.io, Hole.io, Shell Shockers and MooMoo.io. They are free, multiplayer and run straight in your web browser with no download. Most share the same simple idea: start small, grow by collecting points or beating other players, and try to reach the top of the leaderboard. Here is what makes each one fun and how to get started.
In this article
What Are .io Games?
.io games are simple online multiplayer games that run in a web browser. The name comes from the “.io” domain that many of them use; .io is officially the country-code domain for the British Indian Ocean Territory, but tech companies adopted it because “I/O” also means input/output. The trend took off in 2015 with Agar.io, and hundreds of similar games followed.
Best .io Games at a Glance
| Game | Genre | How it works |
|---|---|---|
| Agar.io | Eat-and-grow | Control a cell, eat pellets and smaller players, split to attack |
| Slither.io | Snake | Grow a worm and make other snakes crash into you |
| Diep.io | Tank shooter | Level up your tank and choose upgrade classes |
| Krunker.io | First-person shooter | Fast, pixel-style FPS matches with classes |
| Skribbl.io | Drawing and guessing | Draw a word while others guess, like Pictionary |
| Paper.io | Territory | Claim land by drawing loops, without getting cut off |
| Hole.io | City-eating | Be a black hole that swallows a city |
| Shell Shockers | Egg FPS | Egg characters battle in a first-person shooter |
| MooMoo.io | Survival | Gather resources, build bases and defend them |
| Zombs Royale | Battle royale | A 2D top-down battle royale |
The Classics
Agar.io
The game that started the craze. You are a small cell in a petri dish; eat pellets to grow, swallow smaller players and avoid bigger ones. Press space to split and launch at enemies. It is simple to learn and very hard to master.
Slither.io
A multiplayer take on the classic snake game. Eat glowing orbs to get longer, boost to cut in front of rivals and collect the orbs they leave behind when they crash.
Diep.io
You control a tank in an arena, destroying shapes and other players to earn experience. As you level up, you choose upgrades and tank classes, from long-range snipers to multi-barrel bullet sprayers.
Best .io Games for Friends
Skribbl.io
A free online Pictionary game. Create a private room, share the link and take turns drawing while others guess. Great for family calls, classrooms and parties.
Krunker.io
A fast first-person shooter with blocky graphics, multiple classes and custom maps. It runs smoothly even on older laptops.
Shell Shockers
A cartoonish shooter where every player is an egg. It is a popular choice for quick matches with friends.
Relaxing and Strategy .io Games
- Paper.io: draw loops to claim territory, but your trail is vulnerable until you return to your zone.
- Hole.io: a black hole that grows by swallowing cars, people and buildings in a timed round.
- MooMoo.io: a survival game where you farm resources, build walls and defend against other players.
- Wings.io: pilot a plane in top-down dogfights.
- Bonk.io: a physics game where you knock other balls off the map.
Tips for Playing .io Games
- Start safe. Most .io games punish risky early moves. Grow slowly first.
- Use the edges. Map edges can protect you from being surrounded.
- Play on a stable connection. Lag is the biggest cause of sudden losses.
- Check the server region. Choose the closest server for the lowest ping.
- Watch for ads and pop-ups. Play on the official game sites and avoid “unblocked” mirror sites that may carry harmful ads.
Are .io Games Safe for Kids?
Most .io games are cartoonish and simple, but they are online and multiplayer. Player names and chat can include inappropriate language, and many sites show ads. For younger kids, choose games without chat, such as Paper.io or Hole.io, use private rooms in Skribbl.io and review each game’s rating and settings first.
Frequently Asked Questions
What was the first .io game?
Agar.io, released in 2015, is widely credited with starting the .io game trend.
Are .io games free?
Yes. Almost all .io games are free to play in a browser. Some offer optional cosmetic purchases or remove ads for a fee.
Can I play .io games on my phone?
Yes. Many popular .io games, including Agar.io, Slither.io and Paper.io, also have mobile apps.
The Bottom Line
.io games are quick, free and surprisingly addictive. Start with the classics, Agar.io and Slither.io, try Skribbl.io with friends and pick Krunker.io if you want action. For more gaming guides, visit The Urban Splatter.
