Tunnel Flip
One control. Tap, click or press space to swap between the floor and the ceiling. Everything else is timing.
Works with touch, mouse and keyboard. No sound, no sign-up, nothing to install. Prefer an endless practice run? There is a gravity flip runner on this site too.
Run over
Liked that? The iPhone game this is based on goes a lot further. See Fluxo on the App Store.
How it works
- Flip any time. You can flip again in mid-air, which is how you get through two obstacles that sit close together.
- Three things can stop you. Spikes on the floor or ceiling, tall walls with a gap on one side, and blocks floating in the middle that you pass by staying on a surface.
- Every 8 points the tunnel changes. A speed surge, a run of spikes, then a breather, in that order.
- Close calls count. Slip past with very little room and your close-call streak goes up. It is shown next to your score when the run ends.
- Today's course is shared. It is built from the date, so a friend who plays today gets exactly the same tunnel. Free run is different every time.
The full game, on iPhone
Tunnel Flip is a small browser take on Fluxo: Gravity Runner. The app is where the idea is built out:
- More to dodge: crushing pistons and timed laser gates as well as spikes, walls and blocks
- Sectors with their own rules, and a Fever streak that doubles gold for six seconds
- Flux Dash, a charge you fill with orbs and spend to smash through a stretch
- Classic, Hyper and Zen modes, plus a daily challenge course
- 18 pixel-art pilots to unlock, and it plays offline with no account
Free to download for iPhone, with optional in-app purchases. Feature list taken from the app's App Store description, checked 10 November 2026.
Questions
Is the daily course really the same for everyone?
Yes. The obstacles are generated from the calendar date in UTC, so two people who play on the same UTC day meet the same obstacles in the same order.
Does Tunnel Flip save or send my score?
Your best score is stored only in this browser. Nothing is sent anywhere, and clearing your browser data removes it.
Is this the same game as Fluxo on iPhone?
No. Tunnel Flip is a small browser game built on the same idea, flipping gravity with one tap. Fluxo: Gravity Runner is the full iPhone game, with more obstacle types, sectors, three modes and unlockable pilots.