Mood
💡 Clever
You will want to know how they built it.
357 sites · page 2 of 8
Sixty seconds to forge the Mona Lisa with a mouse, then a pixel-by-pixel score telling you exactly how badly it went.
- 2 min
- Desktop
Curated stumble button that sends you somewhere good rather than somewhere random, with categories if you are feeling fussy.
The word-association board game in a free, well-built online room: two spymasters, one grid of code names, nothing to install.
- 10 min
A browser playground for HTML, CSS and JavaScript, plus an endless stream of other people's demos to open, read and remix.
- 1 hr+
- Desktop
Settlers of Catan in a browser tab, complete with the trade negotiations and the one player who will not give you wheat.
- 10 min
Records a page as you browse it, capturing the parts a crawler cannot — logged-in views, video, anything behind a click.
- 10 min
- Desktop
Sixteen words, four hidden groups, four mistakes allowed. The traps are the entire point and they are very carefully set.
- 2 min
Guess the secret word and be told only how semantically close you got. Rank 4,000 feels like progress, and it very much is not.
- 10 min
Recipes laid out as a table of operations instead of prose, so you can see at a glance what combines with what and when.
- 10 min
- Desktop
Hit the space bar for a five-colour palette, lock the ones you like, hit it again. The whole tool is that loop.
- <1 min
A few hundred browser escape rooms in one filtered shelf, all running in the tab with nothing to install and nothing to buy.
- 2 min
Scores films for you by finding users whose past ratings track yours, then weighting their opinions. Recommendation with the maths shown.
- 10 min
- Desktop
Translates a cron expression into plain English as you type it, then tells you when it will next fire. Ends a very specific argument.
- <1 min
- Desktop
Wordle in reverse: you are handed the green and yellow clues and have to reconstruct the guesses that could have produced them.
- 10 min
An explorable on how ideas and riots spread through a social network, with the contagion thresholds under your control.
- 10 min
Chain encoders and classical ciphers together and watch text transform between formats at each step.
- <1 min
- Desktop
Builds a gradient visually and hands over the CSS, including the awkward multi-stop and radial cases.
- <1 min
Recreate a target image in as few characters of CSS as possible, then watch somebody do it in half as many.
- 1 hr+
- Desktop
Tower defence from the villain's side, defending your gems from heroes using demons, orcs and the undead.
- 10 min
- Desktop
GCHQ's public knife for decoding and decrypting data, built by dragging operations into a pipeline.
- 10 min
- Desktop
A hundred consecutive interface prompts delivered by email — the sign-up flow, the 404 page, the calculator, day by day.
Fly a helicopter, wall off territory with towers, then defend the shape you just drew from everybody else.
- 10 min
- Desktop
German satirical news delivered with a completely straight face, plus a weekly video bulletin, running since 2008.
- 10 min
The 2007 original that turned maze building into a genre, played across a desktop with the icons still sitting on it.
- 10 min
- Desktop
Alarming research site about a chemical found in tumours, acid rain and every reservoir on earth. The chemical is water.
- 2 min
An avatar library where you can dial through a dozen illustration styles and copy the result straight out as an image.
- <1 min
The same six panels of clip-art dinosaurs every day since 2003, with entirely different words in them each time.
Turns any image into one-bit dithered grain, with a choice of classic algorithms and a two-colour palette picker.
- 2 min
Dithering aimed squarely at the chunky, ugly end of the spectrum, with palettes lifted from old hardware.
- 2 min
Serious dithering workbench with dozens of algorithms, custom palettes, live preview and a video mode as well.
- 10 min
- Desktop
An interface that forbids clicking entirely and makes you navigate by hovering, which is far stranger than it sounds.
- 2 min
- Desktop
Dashcam footage of a city loop with the local radio playing over it, so you can drive slowly through Istanbul while answering email.
- <1 min
- Sound on
- Desktop
JavaScript demos in 140 characters. The gap between how little code there is and what appears is the whole appeal.
- 10 min
- Desktop
Interactive classroom illusions you can drag, toggle and pause, which makes the effects considerably harder to dismiss.
- 10 min
- Desktop
A museum of Google easter eggs that Google removed — gravity, the barrel roll, the mirrored search — all restored and working.
- 10 min
- Desktop
Every Google emoji mashup, searchable — pick two and get the official illustrated hybrid back as a PNG.
- <1 min
Upload a photograph and it rebuilds the entire thing out of emoji, colour-matched one tile at a time.
- 2 min
- Desktop
Search, click, paste, with nothing else on the page competing for attention, which is precisely the point.
- <1 min
Slide across a stack of time zones and see the hour for everyone at once. The quickest way to find a meeting slot that spans continents.
- <1 min
All 2^122 version-four UUIDs listed in order with a working search box, on a page that should not be able to exist.
Design a creature from joints and muscles, then watch a genetic algorithm spend hundreds of generations teaching it to limp.
- 10 min
- Desktop
Hundreds of playful projects from Google and creative coders: AI drawing games, music toys and odd interfaces, most of them running in the browser.
- 1 hr+
- Desktop
The hub for playable posts — effectively the index for the entire genre of learn-by-fiddling essays.
- 1 hr+
- Desktop
An idle game built on actual differential equations, with optional theory levels that teach you the mathematics as you climb.
- 1 hr+
Home of the GROW games, where you choose an order for a handful of objects and then watch a tiny world assemble or fail.
- 2 min
- Desktop
Ugly, ancient, and still better than everything else at cutting, resizing, reversing and optimising a GIF.
- 2 min
FactNet
AltFShort, sourced facts arranged so one leads into the next. Built for the specific pleasure of learning something you can repeat.
- 10 min
Full-screen fake update screens for every operating system, including the blue one, with a bar that never finishes.
- <1 min
- Desktop
How we picked these
Every entry in Detour is hand-sorted rather than scraped: filed under one category, given one to three moods, and placed in a time band for how quickly it pays off. The practical facts — cost, sign-up, sound, device and whether it is safe at a desk — are recorded per site and shown on every card, so you can rule things out before you click.
Clever websites: questions
How many sites are in clever websites?
357 sites, each hand-sorted by category, mood and how long it takes to pay off. 8 of them are AltF originals that run right here.
Which of these sites are free with no sign-up?
347 of the 357 are free and need no account. 1 is paid or freemium, and the card says so.
Do these sites work on a phone, and are they safe for work?
185 of 357 work on a phone; the rest are desktop only. 357 are safe for work and 323 work with the sound off.