Poetical Engine
@chenzefeng09
Building small free web tools.
Grassy Knees lists real things to do with kids — library programs, museum family days, festivals, nature walks — across 32 US metro areas. Every listing links to the organizer’s own page and shows the date we last checked it. Free to browse without an account, with a weekly weeke ... more
Free background remover that runs on your device. Click-to-erase color mode for plain backgrounds, plus an optional on-device AI model (~17MB) for complex scenes. Feather edges, compare before/after, fill any color, download transparent PNG. English, Spanish, Indonesian — photos ... more
Free online microphone test in the browser: live level meter, oscilloscope waveform, stereo/mono channel readout and device picker. Record a short clip that never leaves your device. Built with Astro on Cloudflare Workers + Web Audio API — no upload, no account.
Free download and upload time calculator. File size x connection speed, adjusted by a real-world efficiency factor so the estimate is honest, not brochure math. Reverse mode: how much fits in X minutes. English and Spanish. Built with Astro on Cloudflare Workers — free, no signup ... more
Free resolution scaler that runs entirely in the browser. Pick a source WxH and a target box, choose fit / fill / stretch, or scale by percentage. Generates standard resolution ladders, checks social-media presets, and tells you whether a source fits without upscaling. Built with ... more
CronCalc translates cron expressions to plain English and shows the next run times instantly. Paste any 5 or 6-field expression, get a human-readable schedule, next 10 executions, and common mistakes flagged. Built with Astro on Cloudflare Workers.
PowerBill converts appliance watts to monthly kWh and cost at your local electricity rate. Pick your country, get the right tariff, see exactly what your devices cost to run. Built with Astro, deployed on Cloudflare Workers.
PixelCalc computes screen pixel density (PPI), megapixels, print size at any DPI, and aspect ratios. Type a resolution, get exact math plus a live CSS-vs-device-pixel readout. No sign-up, no uploads — everything runs locally in the browser.
Conservative shelf-life reference for 200+ foods: pantry, fridge and freezer times, opened-vs-unopened splits, spoilage signs and an is-it-still-good checker — USDA/FDA-aligned.
Free JSON formatter and validator: pretty-print, minify, sort keys, tree view and line/column error pinpointing. 100% in your browser — nothing leaves your device.
Free easy grader for teachers: total questions + wrong answers in, percentage and letter grade out on strict/standard/lenient scales, with a printable grading chart for 0 to N wrong.
Memory test where you try to beat a chimpanzee. Numbers flash, hide, tap them back in order. Based on the 2007 Kyoto University study where Ayumu the chimp kept ~80% accuracy at 210ms flashes. 3 strikes, escalating speed, ?r= challenge links to dare friends. Stats stay on your ... more
A small multilingual dictionary of classic dream symbols — teeth, water, flying, snakes, being chased — with what different interpretation traditions say about them. In five languages. Free, no signup. Built with Astro on Cloudflare Workers.
Free baby growth percentile calculator for ages 0-5. WHO and CDC charts for weight, length/height and head circumference, plus a private growth log. No signup, data stays in the browser. Built with Astro on Cloudflare Workers.
Free WiFi QR code generator. Type your network name and password, get a scannable QR code and a printable guest card. Runs 100% in the browser, nothing is uploaded. Built with Astro on Cloudflare Workers.
Free online ID photo maker for badges, student IDs and cards. Upload a photo, crop it with head-position guides, check the background, and download the exact size plus a 4x6 print sheet. Runs entirely in the browser — photos never leave your device.
🗓️ Activity log
3 posts last 4 weeks