Sign in with Steam, open Matches, and drop your .dem file onto the upload area — compressed downloads are accepted. The server parses the demo once into match metadata, a binary player-snapshot stream and grenade data, then the browser rebuilds the match in 3D. Press R in the replay to open the review panel and work through its summary, rounds, events and utility tabs.
Which demo should you upload first?
Upload a close loss, not a highlight match. A blowout tells you almost nothing you can act on; a close loss concentrates the rotations, utility and spacing errors that repeat every week. If you are choosing between two matches, take the one where you remember being confused rather than the one where you remember being unlucky.
If you do not have the file yet, get it from the service where the match was played — the source-by-source steps are in how to find and download a CS2 demo file. Extract compressed downloads before you look for the .dem.
Upload the demo, or import it by share code
There are two routes into the library, and they cost you different amounts of bandwidth:
- Manual upload. Open Matches and drop the file onto the upload area. Large demos are sent in parts rather than as a single request. The file picker accepts
.demplus the compressed forms providers actually serve —.gz,.zstand.bz2— and the server decompresses them for you, so you never have to unpack one by hand. - Server-side import. Where the integration is configured, paste a CS2 matchmaking share code or a FACEIT match link and the server fetches the demo itself. Nothing large leaves your machine. A share code is not a demo file — it identifies a match that an enabled integration can retrieve. Connecting your CS2 match-history authentication code lets recent matches be pulled in the same way.
What does the parser actually recover?
Parsing is a one-time cost per demo. The server walks the file once and writes a cache, so reopening the match later is immediate. What it writes is worth knowing, because it defines the ceiling on every analysis you can do afterwards:
- Match metadata — map, players, teams, round boundaries, the score model that survives side swaps, and the kill, bomb-plant and defuse events.
- A binary snapshot stream — per player, per sample: position, view angle, health, armour, crouch state, active weapon and money. Samples are taken every two demo ticks, which is 32 snapshots per second on a 64-tick demo, and playback interpolates between them.
- Grenade data — every throw indexed by round and type, with its full trajectory, and the voxel smoke data that lets smokes render as real volumes rather than sprites.
Anything outside that set is not recoverable later by re-reading the cache. That is the honest reason some questions ("what did they say on comms?") have no answer in any demo tool.
How do you use the match review panel?
The review panel docks to the left of the 3D stage and organises the parsed match into four tabs. Press R to open or close it. Use it as a checklist rather than a scroll:
| Tab | Use it to |
|---|---|
| Summary | Confirm map, score, sides and per-player performance before drawing any conclusion. If the names or map are wrong, you opened the wrong file. |
| Rounds | Jump straight to the rounds that decided the match instead of scrubbing from tick zero. |
| Events | Step through kills, deaths, bomb plants and defuses, and read the timing windows between them. |
| Utility | Inspect grenades by round and type, jump to an individual throw and draw its complete trajectory in the world. |
The panel compacts the 3D stage rather than covering it, so the replay stays visible while you navigate. The keyboard shortcuts that pair with it — Q/E for previous and next event, Shift+Q/E for deaths, Shift+arrows for rounds — are listed in the controls reference.
Turn analysis into a repeatable mistake
Do not review every second with equal attention. Deaths after an advantage, late utility, site entries, post-plant spacing and retakes carry most of the improvable signal. One-off aim misses do not.
When a death matters, stop describing it and play it. Opening it as a Replay Moment rebuilds the situation with the recorded positions, utility, health and clock and hands you control, so you can test whether the alternative you imagined actually works. Attempts are graded, so "I would have won that" gets checked instead of assumed.
For the round-by-round method around all of this, use how to review a CS2 demo. For utility specifically, use how to review CS2 smokes, flashes and grenades.
Privacy, retention and sharing
Private demos and the parsed caches derived from them are available only to the account that uploaded them. Account controls let you delete an individual demo or your whole account, and export your data. Read the current privacy notice for the authoritative retention terms — guide copy does not override it.
For team review, screenshots and share links are usually clearer than sending a whole VOD: a single reconstructed viewpoint puts everyone on the same round and the same angle. Those tools are part of PRO.
Frequently asked questions
How big a CS2 demo can I upload?
Free signed-in accounts can upload demos up to 400 MB and add one demo a day, whether it arrives as a file or as a pasted match link; free demos are kept on the server for 48 hours. PRO raises the limit to 800 MB per demo, with unlimited demos kept for 30 days. The size limit applies to the decompressed demo rather than to the compressed download you started with.
Can I import a CS2 demo with a share code instead of uploading?
Where the server integration is configured, you can paste a CS2 matchmaking share code or a FACEIT match link and the server fetches the demo directly. A share code is not itself a demo file, it identifies a match that an enabled integration can retrieve.
What does the parser extract from a CS2 demo?
It extracts match metadata, a binary snapshot stream of player position, view angle, health, armour, crouch state, active weapon and money, plus round boundaries, kill and bomb events, and every grenade throw with its trajectory.
Are uploaded CS2 demos private?
Private demos and the parsed caches derived from them are available only to the account that uploaded them, and account controls let you delete an individual demo or your whole account.