How to watch a CS2 demo without opening the game

Watching a demo in Counter-Strike 2 means launching the game, loading the map and stepping through the match with the console. That is fine for a quick look and annoying for everything else: the game has to be installed, the demo UI has no proper timeline across rounds, and you cannot do it on a machine that does not run CS2.

The short way

Open demolens.org in a desktop browser.
Drag your .dem, .dem.gz or .dem.zst onto the page, or click to pick it.
Wait a few seconds while it parses, then use the round timeline.

The demo is parsed locally by a WebAssembly build of the demo parser. Nothing is uploaded, there is no account, and the file stays on your disk.

What you can see

2D replay on the map radar, with zoom, pan and follow-player
Round timeline, kill feed, damage and HP, economy per round
Grenade trails, flash effectiveness and utility damage
Voice chat playback and in-game chat with on-device translation (FACEIT demos)
Per-player stats compared against professional percentiles

What it is not

It is a 2D tactical view, not a 3D first-person replay. If you need to judge a crosshair placement frame by frame, the in-game demo viewer is still the right tool — the console commands are worth knowing for that.

Requirements

A desktop browser (Chrome, Edge or Firefox). Voice playback needs the WebCodecs audio decoder, which Chrome and Edge provide. Phones are not supported: the replay view is a wide two-column layout, and a phone has no access to your demo files anyway.

Where to get the demo file

From the game: Watch tab → Your Matches → Download, which lands in the replays folder. From FACEIT: the match room offers a download.

DemoLens is a community project, not affiliated with or endorsed by Valve Corporation or FACEIT. Counter-Strike is a trademark of Valve Corporation.