About Bridge Builder
Bridge Builder is a subset-sum puzzle with a construction theme. A river gap has an exact width and you have a pile of planks of different lengths. Pick the planks whose lengths add up to precisely the gap, then test the bridge. Too short or too long and it collapses.
How to play
- Tap planks to add them to the bridge.
- The bridge total is shown next to the gap width.
- Press Test bridge when the total matches the gap.
Tips and strategy
- Start with the longest plank that fits inside the gap.
- Work out what remains and look for a plank or pair that fills it.
- Parity helps: an odd gap needs an odd plank.
Levels, stars and XP
Finish a level to earn one to three stars and XP towards your player level. Replay any unlocked level to improve your stars. From level 151 the game enters endless mode, where each level is a remix of an earlier one with fresh colours and a slightly higher difficulty.
Frequently asked questions
- How do I play Bridge Builder?
- Tap planks to add them to the bridge. The bridge total is shown next to the gap width. Press Test bridge when the total matches the gap.
- What is a good strategy for Bridge Builder?
- Start with the longest plank that fits inside the gap.
- How many levels does Bridge Builder have?
- Bridge Builder has 150 levels that rise gradually in difficulty. After level 150 the game continues without end: levels are drawn from the first 150 in a newly shuffled order, with new colours, flipped or rotated layouts and a small difficulty boost, so the level number keeps increasing.
- Is it free to play?
- Yes. Bridge Builder is completely free and runs in your browser on phones, tablets and computers. No download or account is needed.
- Does my progress save?
- Your level, stars and XP are saved in your browser on this device. Clearing your site data will reset them.