Overview

osu!lazer is the free, open-source, cross-platform client for osu!, one of the most played rhythm games on PC. Hit circles appear on screen in time with a song and you click them, drag along sliders and spin spinners to build a combo, accuracy and score — a formula that turned an obscure 2007 hobby project by Dean “peppy” Herbert into a game with a community of millions of player-made beatmaps. lazer is the modern rewrite of that client: it replaces the old .NET Framework original with a fresh cross-platform codebase that runs on Windows, macOS, Linux and Android from the same source, and it is developed openly on GitHub under the MIT licence.

Key Features

• Four game modes in one client — osu!standard (click the circles), osu!taiko (drumming), osu!catch (catch the fruit) and osu!mania (a vertical-scrolling keyboard mode).
• Huge community beatmap library — browse and download from the official osu! beatmap listing, or drop in any .osz file; imports are instant and searchable from inside the game.
• Cross-platform and open source — official builds for Windows, macOS (Intel and Apple Silicon), Linux (AppImage) and Android, all from the MIT-licensed source at github.com/ppy/osu.
• Deep customisation — import interface skins, storyboards and hitsounds, or build your own; the editor for creating beatmaps is built into the client.
• Online features — global and local leaderboards, replays, multiplayer rooms, spectator mode and in-game score submission, all tied to a free osu! account.
• Date-based releases — the client ships a new build roughly every week (the current release is 2026.1005.0-lazer, dated 5 October 2026), and updates itself in place.

Why Use It

It is the reference implementation of a rhythm game that has outlived almost every commercial rival, and it is genuinely free: no purchase, no ads, no gameplay locked behind a paywall. The optional osu!supporter subscription is a donation-style perk (extra profile and download options) rather than a requirement to play. Because the client is open source you can read exactly what it does, run your own builds, and play on Linux and Android without a wrapper. If you have ever wanted a rhythm game that respects its players and has a decade of music written for it, this is the one.

Use Cases

• Playing ranked and unranked beatmaps solo and chasing a higher score on the global leaderboards.
• Multiplayer lobbies with friends or strangers across any of the four game modes.
• Creating your own beatmaps with the built-in editor and sharing them with the community.
• Practising with replays, playback controls and per-map difficulty mods to improve accuracy.
• Playing across devices — the same account and scores on desktop and Android.

Platforms

Windows, macOS (Intel and Apple Silicon), Linux (AppImage; also available on Flathub) and Android. A free osu! account is needed for online features such as leaderboards, score submission and multiplayer; offline play works without one.

Licence

Open source — MIT. The client source code is released by ppy Pty Ltd under the MIT licence, so you may use, modify and redistribute it, including commercially, provided the copyright notice is kept. This covers the game client only: the official online service the game connects to is operated by the project, and user-made beatmaps carry their own licences from their creators.

Website

osu.ppy.sh · Source: github.com/ppy/osu

Similar open-source games

• StepMania — open-source rhythm and dance game with a built-in stepchart editor and a huge community song library.
• Frets on Fire — free guitar-style rhythm game you play with the keyboard, with its own song editor and chart library.