Rules

1 · The run

A run starts when you press Space and ends when the dinosaur hits something. Jump with Space or ↑, duck with ↓. On a touch screen, tap to jump and hold the duck control.

The dinosaur accelerates the entire time. Nothing else about the game changes — obstacle spacing is measured in distance, not time, so a faster run is not a denser one. Speed alone is the difficulty.

Runs are unlimited and free. There is no energy meter, no cooldown, no daily cap, and no way to pay for another attempt. A bad run costs you nothing but the twenty seconds you spent on it.

2 · Your score

Score is distance. It ticks up while you are alive and stops the instant you are not.

Your rank is set by your single best run of the day — not your total, not your average, not how many times you played. Fifty mediocre runs do not add up to one good one.

Two entries on the same score are separated by who reached it first. Getting there early is worth something, and defending a lead is a real position rather than a formality.

Submitting a run that does not beat your own best changes nothing. It is not recorded as a regression and it does not cost you your place.

3 · The daily reset

The board clears at 00:00 UTC, every day, with no exceptions and no grace period. The countdown at the top of every page is the authority.

A reset does not delete anything. The day that just ended is written into the Hall of Fame permanently, and the day that just started begins empty for everyone at the same moment.

There are no seasons, no leagues, and no carry-over. Yesterday's score has no bearing on today's rank.

4 · The champion's day

Whoever holds #1 when the board clears becomes the champion for the following day. That means:

• The champion strip at the top of every page on this site, for twenty-four hours.
• A permanent Hall of Fame entry, with the score and the traffic it earned.
• Outbound clicks from both, counted and shown publicly.

Then the entry retires undefeated and can never be entered again. This is the part people ask about most, so plainly: retirement is permanent, it is not a cosmetic badge, and it exists so that a single dominant player cannot hold the strip forever. Winning takes you off the board.

5 · How a score is verified

The number your browser reports is treated as a claim, not a result.

Every run submits the input trace that produced it — the frames on which you jumped and ducked. The server replays that trace through the same deterministic simulation the game runs locally. The score counts only if the replay dies on the same frame with the same score.

The simulation uses a fixed timestep and integer arithmetic, so the replay is exact rather than approximate. A run is rejected if any of the following is true:

• The replay disagrees with the claimed score or death frame.
• The trace contains inputs that could not have come from the stated device.
• The run ID has already been used, or is more than fifteen minutes old.

A rejected run is dropped silently and does not affect your standing. Repeated rejections from one source are rate limited.

6 · What you can attach

One run carries one entry: a product URL or a social handle. Both are shown the same way and ranked the same way.

• An entry already on the board can be entered again — you are playing to beat its own best, not to create a duplicate row.
• A retired champion cannot be entered again, by anyone, including whoever originally entered it.
• You do not need an account. Attaching a handle is how you claim an entry as yours.

You can also play with nothing attached. It will not be ranked, and that is a perfectly normal way to use this site.

7 · Moderation

Entries are removed for a short and boring list of reasons: malware or phishing, sexual content involving minors, content that targets a private individual, impersonation of a person or company, and links that redirect somewhere other than what was entered.

Removal takes the entry off the board and out of the running for that day. It does not affect anyone else's rank — positions below simply move up.

We do not remove entries for being competitors, for being unpolished, or for being unpopular.

8 · Reporting an entry

Every row on the board can be reported. A report asks for the entry and one sentence about what is wrong with it; nothing else is required and no account is needed.

Reports are reviewed by a person. A malicious link is acted on immediately; everything else is looked at in order. Filing a report against a rival is not a strategy — it does not pause their run or hide their row while the report is open.