Slope Game
Slope is a 3D ball game by Rob Kay, first released in 2014: a ball rolls down a road of green tiles and you steer it left and right to keep it on the road and away from red blocks. Press Play on the frame above to play Slope online for free, with nothing to download, and your best score goes on the leaderboard beside the game.
| Original game | Slope by Rob Kay, published by Y8 |
|---|---|
| First released | Kongregate, September 2014; added to Y8 on September 30, 2014 |
| Version here | Unofficial web build; the menu reads V1.0 |
| Controls | Left and right arrow keys, or A and D |
| A run ends | When the ball falls off the road or hits a red block |
| Score | The number at the top of the screen, counting up from 0 after the tunnel |
| Cost | Free, no download, no account |
| Leaderboard | Beside the game (the LEADERBOARD button inside the game shows an empty table) |
On this page: what Slope is, how to play, tips, our test runs, the leaderboard and the FAQ.
What is the Slope game?
Slope is a 3D ball game played in a web browser. You steer a green wireframe ball that rolls by itself down a road of glowing green tiles, past red blocks, and the run ends when the ball falls off or hits a red block. The game has no levels and no finish line, so the goal is to get as far as you can and beat your best score.
Rob Kay, the lead designer of the original Guitar Hero, made Slope. He released it on Kongregate in September 2014 as robkaySF, with the description "Speed down a randomized slope. Avoid death for high score." Y8 added it on September 30, 2014. In a video from March 2026, Rob Kay says he made the game during a 30-minute train commute.
On his website, Rob Kay says Slope has passed 150 million plays, and Y8's Slope page showed about 149 million plays on November 13, 2026. The Credits screen of the Y8 version reads "game by @RobKaySF", "music by @SynthR" and "published by @Y8.com".
Several other games use the name: Slope 2, Slope 3, Slope Run, Slope Rider and Slope Plus are different games or modified versions. Slope100 runs Slope itself. The version on this page shows V1.0 in its menu and has no Y8 buttons or Credits screen; Y8's own build is on the Slope Y8 page.
How to play Slope
- Press Play on the frame at the top of the page. A loading screen reads SLOPE GAME, and then the menu shows PLAY, SETTINGS and LEADERBOARD.
- Press PLAY. The run starts in a tunnel, under the hint "STEER WITH ARROWS OR A/D".
- The ball rolls forward on its own. Use the left and right arrow keys, or A and D, to keep it on the road.
- About five seconds in, the tunnel ends and the score appears at the top of the screen. From here on, red blocks sit on and beside the road.
- When the ball falls or hits a red block, the GAMEOVER screen shows YOUR SCORE with PLAY AGAIN, LEADERBOARD and BACK. PLAY AGAIN starts the next run at once.
Slope controls
| Key | What it does |
|---|---|
| Left arrow or A | Steers the ball left |
| Right arrow or D | Steers the ball right |
| Space, up arrow, down arrow, W, S | No effect we could see (2 test runs each) |
| Esc or P | Did not pause the game (2 test runs each) |
| Mouse button held on the game | Did not steer (4 test runs) |
What ends a run
A run ends when the ball rolls off the edge of the road or touches a red block. In the two test runs where we saw the ball touch a red block, the run ended right there. The GAMEOVER screen comes up about three seconds after the run ends.
How the score works
The score is the single number at the top of the screen. It starts at 0 when the ball leaves the opening tunnel, about five seconds into the run, and goes up by one at a time; the game does not say what it counts. In one timed run, the counter reached 5 about 7.4 seconds after it first showed 0. The GAMEOVER screen repeats the number as YOUR SCORE.
"SPEED UP" appears at the bottom of the screen about five seconds into a run, and in our longest run it appeared again at about nine seconds. Y8's Slope page says the ball moves faster the longer you survive. We have not measured the ball's speed ourselves.
Settings
The SETTINGS button in the menu has a SOUND box to turn sound on or off and a VOLUME slider. There are no control or graphics options.
Tips for longer Slope runs
- Do not hold a steering key down. In all 15 of our test runs that held a steering key for two and a half seconds right after the tunnel, the ball ran off the edge within about two seconds. Let go as soon as the ball has moved.
- Be ready when the tunnel ends. In one of our runs, a red block was already on the road about six seconds in, a second after the tunnel.
- Use the Fullscreen button under the frame for a bigger view of the road ahead.
- After a run ends, press PLAY AGAIN to go straight into the next one without reloading.
Our Slope test runs
On November 13, 2026, we logged 38 test runs of the version on this page in desktop Chrome at 1440 by 900 pixels, timed from the moment we pressed PLAY. A script sent the key presses. In the steering runs it held one key for two and a half seconds, starting about 5.4 seconds into the run, just after the tunnel, and it tapped Esc and P once each. We also held the mouse button on each half of the game.
| What we did | Runs | Run ended at | Score |
|---|---|---|---|
| No key, or a key with no effect | 19 | 6.4 to 14.3 s | 1 to 5 |
| Held the mouse button | 4 | 7.4 to 12.4 s | 2 to 5 |
| Held left arrow or A | 9 | 7.1 to 7.5 s | 1 |
| Held right arrow or D | 6 | 7.1 to 7.4 s | 1 |
We ran every test on a desktop computer and have not tested a phone or tablet.
Slope100 leaderboard
The leaderboard beside the game shows the top 10 Slope100 players and updates when a run ends. You start with the name the game picks, Player plus five letters and numbers, and you can type a new one in the YOU row. The board keeps one best score for each player and knows you by your browser.
The leaderboard counts only runs played on Slope100, so it is not a world record. The community leaderboard on speedrun.com keeps checked records and ranks each version of Slope separately. The top 100 Slope100 players, and those records, are on the Slope100 high scores page.
More Slope on Slope100
- On a school or work computer, try Slope Unblocked. It runs the same version as this page and covers what to do if the game does not load.
- For Y8's own build of Slope, with its Login button and Credits screen, open Slope Y8.
- To see where your score ranks, and the speedrun.com records for each version, open Slope High Score.
Slope game FAQ
Is Slope free to play?
Yes. Slope on Slope100 is free, runs in your browser and needs no account. Press Play on the frame at the top of this page to start.
Who made the Slope game?
Rob Kay made and first released Slope. He put it on Kongregate in September 2014 under the name robkaySF, and Y8 added it on September 30, 2014. Rob Kay was the lead designer of the original Guitar Hero, and he has said he made Slope during a 30-minute train commute.
Where can I play the Slope game?
You can play Slope at the top of this page in a desktop browser, free and with nothing to install. Y8's own version is on the Slope Y8 page of this site and on y8.com.
What are the controls in Slope?
Steer left with the left arrow key or A, and right with the right arrow key or D. The ball rolls forward by itself, so steering is all you do. In our tests Space, the up and down arrows, W and S had no effect we could see, and holding the mouse button on the game did not steer.
Can you pause Slope?
We found no way to pause the version on this page. It has no pause button, and Esc and P did not stop the ball in our tests.
Is there an end to Slope?
Slope has no finish line that we know of. Y8 describes it as an endless 3D track, the game's menus have no levels, and each run ends when the ball falls off the road or hits a red block. Our longest test run lasted 14.3 seconds, so we have not seen a late stage ourselves.
Is the Slope game hard?
It is easy to lose early. With no steering, our test runs ended after 6 to 14 seconds with scores of 1 to 5, while the top checked scores on speedrun.com range from 210 to 601 depending on the version.
What is a good score in Slope?
There is no official scale. With no steering at all, our test runs scored 1 to 5. The Slope100 high scores page lists the best score of each player on this site.
What is the highest ever score on Slope?
On November 13, 2026, the highest checked score on the speedrun.com leaderboard for Slope was 601 points, on the V1.3 Unblocked version. The Slope100 high scores page explains the record and why bigger numbers come from Slope Plus.
What is that green ball game?
It is probably Slope. In Slope you steer a green wireframe ball down a road of glowing green tiles on a black background, past red blocks. You can play it at the top of this page.
Do I need to download Slope?
No. Slope runs in your browser with nothing to install. The browser loads the game files from slope100.com the first time you press Play.
Can I play Slope on a phone?
We have not tested Slope on phones or tablets. The controls we confirmed are keyboard keys, and holding the mouse button did not steer in our tests. On phones, the leaderboard beside the game is hidden.
Is Slope100 the official Slope site?
No. Slope100 is an unofficial site run by PLAY100, and it is not affiliated with Rob Kay or Y8.
Tested and written by PLAY100, a small web game studio from Vietnam. Last checked: .