About this game

Spring Jump is built on Hooke's law: the force a spring returns rises in proportion to how far it is compressed, and the energy it stores rises with the square of that compression. In practice, a full charge does not launch you twice as high as a half charge — it launches you about four times as high.

That squared relationship is why the game rewards committing. Small nervous hops barely clear the next platform, while the floor beneath you rises faster the higher you get. The platforms themselves vary: bouncy pads add speed, ice gives you nothing to charge against, and crumbling pads collapse under you while you stand there.

How to play

  1. Hold Space while standing on a platform to compress the spring. A meter shows the charge.
  2. Release to launch. Longer charges store disproportionately more energy.
  3. Steer left and right while airborne. The screen wraps, so drifting off one side brings you back on the other.
  4. Land on fresh platforms to keep a chain bonus going.
  5. The red floor rises constantly. The run ends when it catches you.

Physics mechanics

Here is what the simulation is actually doing while you play.

Hooke's law

A spring pushes back with F = −k·x, where x is how far it is compressed. The energy it stores is ½·k·x², so doubling the compression stores four times the energy.

Energy to velocity

Releasing converts stored spring energy into kinetic energy: ½kx² becomes ½mv². Rearranged, launch speed is proportional to compression times the square root of stiffness over mass.

Projectile flight

Once you leave the platform you are a projectile. Horizontal steering is a small force; the vertical arc is decided entirely by your launch speed and gravity.

Restitution on bouncy pads

The gold pads have a restitution near 0.62 and also add a fixed upward impulse, so they return more than they receive. They are the fastest way to gain height, when you can reach one.

Objective

Climb as high as possible before the rising floor reaches you.

Scoring

  • Height is worth one point per ten world units.
  • Landing on a fresh platform scores 40 points plus 12 per platform in the current chain.
  • There is no score for time spent — only for height gained.

Scores, favourites and play history are stored in your own browser using localStorage. There is no account, no leaderboard and no server: clearing your browser data clears them, and they do not follow you to another device.

Tips

  1. Full charges are worth four half charges. Stored energy goes with the square of compression. Two 50% charges climb far less than one 100% charge.
  2. Charge immediately on landing. The floor never stops rising. Every second on a platform costs altitude you will have to re-earn.
  3. Bouncy pads beat charging. A gold pad gives free height with no charge time. Route towards them even if it means a sideways detour.
  4. Crumbling pads are one-use. Pink pads collapse about half a second after you land. Charge and go, or use them purely as a bounce.
  5. Use the wrap. Drifting off the left edge puts you on the right. A platform that looks unreachable is often easier to get from the other side.

Difficulty

Medium. The first few hundred metres are generous and the platform spacing is wide. Past 1,500 metres platforms narrow, crumbling pads become common and the floor speed roughly doubles, which is where runs usually end.

Features

  • Launch speed derived from stored spring energy
  • Four platform types: solid, bouncy, ice and crumbling
  • Rising floor that accelerates with your height
  • Horizontal screen wrap so a bad drift is recoverable
  • Chain bonus for landing on fresh platforms in sequence

How accurate is this?

Physics Arcade games use simplified, tuned physics built for playability. They are not scientific simulations: forces, masses and timings are chosen because they feel good at 60 frames per second, not because they match measured values. Where a game departs from real-world behaviour in a way that matters, the game page says so.

Spring Jump – FAQ

Why can I not charge in mid-air?

The spring needs something to push against. Charging only works while you are standing on a platform, which is the constraint the whole game is built around.

Does a longer hold always launch higher?

Up to the maximum charge, yes — and disproportionately so, because stored energy goes with the square of compression. Past full charge the meter stops.

What do the pink platforms do?

They crumble. They hold for roughly half a second after you land, then break. They still work as a launch point if you charge quickly.

Can I fall back down to a lower platform?

Yes, and it is often a deliberate tactic if the next platform up is out of reach. The floor will catch up eventually, so do not linger.