Every app below is a single HTML file with everything inline — no install, no account, no server. Each one saves your data in the browser, so it remembers what you put in. This is exactly the kind of thing you build in a session, hands on your own keyboard, in well under an hour. Click any card to try it — and on each app, hit 💬 See the prompts to reveal the plain-English instructions that built it. View all build prompts →
What that recurring meeting really costs — with a live ticker.
📉Cash ÷ net burn → months left, and the date it runs out.
🗒️Capture the call and the why — judge your own judgement later.
🔴Likelihood × impact on a 5×5 RAG heatmap.
🧭Score the three options; get a clear steer.
📊Your portfolio and the one decision each needs.
👥Hires against milestones, with the cost ramp quarter by quarter.
🎯Score the quarter — with a built-in guide for OKR newcomers.
Add books, mark them read, see your year. The canonical starter build.
🔥Tick a habit daily and watch the streak climb. Storage doing visible work.
⛳Log rounds, get a rolling handicap calculated automatically.
🏋️Log sets, and it tracks your personal bests automatically.
Type numbers, get a live chart. Disproportionately impressive for the effort.
🌡️Set a target, log deposits, fill the thermometer.
🕰️Log your hours, see the week as a donut chart.
See how much an extra monthly payment saves in years and interest.
🧭Score a task on five questions, get a clear recommendation.
💷Turn a day rate into real annual and monthly take-home.
⚖️Score options against weighted criteria; see the winner.
🌱Watch steady saving compound into a growth curve.
Who drops which kid where, and when. The relatable hero build.
🧳A reusable list that remembers itself trip to trip.
A timed drill with scoring. Kids love it; so do execs with kids.
🃏Flip-and-match grid with a move counter and best score.
A Pomodoro with a depleting ring and a daily session count.
🗂️Make cards, flip to reveal, and learn anything.
What the same tools do with a bit more time: search and filter, real photos, a detail view, and a form to add your own recipes — all still one self-contained file that remembers everything in the browser. Closer to an afternoon than an hour, but nothing new to learn.
Open it →