About

The Game

Halfslice is a precision slicing game. A shape appears on screen — your job is to slice it as close to perfectly in half as possible. Every player gets the same shape each hour, so you can compare your precision on equal footing.

The maximum score is 100,000, awarded for a Perfect Slice: a split within 0.05% of exactly 50/50. The scoring curve is steep — even a 49/51 split is worth far less than a perfect half. Precision is everything.

Why We Built It

We wanted a game that was genuinely hard to master but fast to play — something you could come back to every day and still find room to improve. Halfslice is that game.

There's no luck involved. No random power-ups or streaks that inflate your score. Just a shape, a slice line, and geometry.

How It Works

Each hour a new polygon is generated from a shared seed, so every player worldwide slices the same shape within that hour. Scores are verified server-side using your stored replay data before being posted to the global leaderboard — available across Hourly, Daily, and Weekly windows.

Your personal stats — best score, perfect slices, daily streak — are saved locally in your browser. Submit a score to the leaderboard to appear alongside players worldwide.

Every score submission includes a compact replay of your slice — the exact coordinates of both click points. The server re-runs the geometry calculation independently and only posts the score if it matches. This makes it impossible to submit a fabricated score without a legitimate replay to back it up. The leaderboard reflects real precision, not exploits.

The Shapes

Each polygon is generated procedurally from a numeric seed that changes every hour. The seed is the same for every player on earth during that window, so everyone is slicing identical geometry. The shapes vary in vertex count, aspect ratio, and rotational orientation — some are convex and easy to read at a glance, others are irregular and require more thought.

Shape generation is designed so that no two consecutive shapes share the same rough form. You won't get a wide flat hexagon followed by another wide flat hexagon. The variety is intentional — part of getting good at Halfslice is learning to read unfamiliar geometry quickly and commit to a slice line before the timer runs out.

Because the shape is identical for everyone, your score is a direct comparison of skill and spatial reasoning — not a comparison of who happened to get an easier shape. That fairness is the foundation the leaderboard is built on.

Scoring in Depth

After your slice, the game calculates the area of both resulting pieces using the shoelace formula — a standard computational geometry technique for finding the area of a polygon given its vertices. The smaller piece's area is divided by the total to get a percentage, and the closer that percentage is to 50%, the higher your score.

The scoring curve is deliberately steep. A 50/50 split earns 100,000. A 49/51 split — visually almost perfect — earns around 67,000. A 47/53 split drops to roughly 30,000. This is intentional: the game rewards extreme precision, not approximate halving. The difference between a good score and a perfect score is a matter of fractions of a percent.

There are six named tiers — Perfect Slice, Incredible, Great, Good, Okay, and Poor — plus a Miss for slices that don't pass through the shape at all or time out. The tier thresholds are shown on the Instructions page, along with tips for improving your accuracy.

Who Made This

Halfslice is an independent project built out of a simple question: could a game be genuinely competitive with zero randomness? No loot boxes, no power-ups, no luck — just a shape and a line. The answer turned out to be yes, and the result is a game that is fast to play but slow to master.

The entire game runs in the browser with no install required. The backend is minimal — a Supabase database stores leaderboard scores, display names, and score replays. Nothing else is collected. The source of truth for your personal stats lives in your own browser's local storage, so your game history stays yours.

If you want to follow along as the game evolves, the blog covers development decisions, game design thinking, and occasional deep dives into the geometry behind the scoring. For bugs, feedback, or general conversation, the Discord and Contact page are both open.

Contact & Community

Have a question, found a bug, or just want to talk geometry? Reach us on Discord or via the Contact page. Common questions are also answered on the FAQ page.