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A daily arithmetic puzzle with a hidden Hard Mode

A daily arithmetic puzzle with a hidden Hard Mode

by kapework·Mar 9, 2026·1 point·0 comments
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AI Analysis

●●SolidCozyCrowd Pleaser

Hidden Hard Mode after solving adds replay value to the classic 24 game formula.

Strengths
  • •No signup, no ads, no friction — just open and play immediately in browser
  • •Dynamic target set computation for Hard Mode creates unique daily challenges
  • •Freeze streak protection earned every 7 days respects player time
Weaknesses
  • •The 24 game itself is a well-known mathematical puzzle with many existing implementations
  • •Daily puzzle format limits engagement to one session per day per player
Category
Gaming
Target Audience

Puzzle game fans, daily challenge enthusiasts, mobile gamers

Similar To

NYT Games · 24 Game

Post Description

I built a small browser puzzle game:

https://make24.app

Each day you get 4 numbers and try to make exactly 24 using +, −, ×, ÷. Each number must be used exactly once, and fractions are allowed.

I like puzzle games that are very easy to start but still genuinely challenging, so I tried to make this one as small and streamlined as possible — no signup, no ads, and not much UI beyond what is needed to play. Much of the AI-assisted coding work was cutting away clutter.

Three moves with no undos in less than 60 seconds constitutes a perfect solve.

After you solve the daily puzzle, a hidden Hard Mode appears. Using the same four numbers, you try to fill as many reachable integer targets as possible before the timer ends.

A few implementation details:

puzzles always have at least one valid solution

Hard Mode computes the reachable target set dynamically

everything runs in the browser

mobile-first, but playable on desktop too

keyboard input works on desktop

Two things I’d especially love feedback on:

Does Hard Mode make sense within the first 10 seconds?

Anything in the UI feel unnecessary or unclear?

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