SHRINK: a zoom game inside real microscope slides

The slide table: pick a slide–

X-WOW · free · no account

SHRINK

Every picture here is a real microscope slide, scanned so sharp you can shrink until you see single cells. Pinch, scroll or press + to shrink.

A postcard shows a real spot. Find it: right place, right size. The bars light up as you get close.

For grown-ups: how it works, privacy and safety

Make a postcard

Can your friend find your spot?

Put the spot in the middle of the screen, at the size you want them to find it.

For grown-ups

What SHRINK is, and what it is not

SHRINK is a free zoom game for curious children (about 7 to 12, and anyone older) built from 32 real microscope slides: the kind of prepared teaching slides schools use, scanned at 20× so that one pixel is 0.5037 µm across. Nothing in the pictures is drawn or generated. The 25 postcards in 6 expeditions were placed one by one on real structures by the AI that wrote the game. Every slide's size and the screen's width are computed from pixels; the sizes in the postcard facts were estimated on the slide and rounded.

For grown-ups: the game keeps progress only in this browser and sends nothing anywhere (privacy).

How it plays, privacy and safety, the slides, the facts

How it plays

  • All the slides lie on one table at their true size. Zooming in is shrinking: the top bar says how wide the screen is and compares it with hairs, dust mites or red blood cells when one of them fits.
  • A postcard shows a real spot. It only counts when the child reaches the right place and the right size, so the game teaches the habit microscopists use: scan at low power, then zoom in to confirm.
  • Before the answer, children name what they found in their own words. The field guide keeps both names: theirs and the scientists'.
  • They can make postcards for each other: frame a spot, press the envelope, send the link. Good for a class treasure hunt.
  • No timers, no scores against anyone, no streaks.

Privacy and safety

  • No accounts, no ads, no tracking, no cookies. Progress is saved only in this browser (local storage, from the first visit) and never sent anywhere. "Start over" in the field guide empties it; clearing the site's data removes it.
  • Everything the game loads, the slide pixels included, comes from x-wow.com itself: no other server is contacted.
  • "Read it to me" uses only a voice that runs on this device; if there is none for the language, the button says so and stays silent.
  • Challenge links carry only a slide, a position and a size: nothing a child types ever goes into one.
  • The slides are animal, plant and fungus specimens. Slides of human tissue and of disease (14) and of mammalian reproductive organs (6) from the same box were left out. On 11 October 2026, 8 more organ slides (heart muscle, stomach, kidney, liver, small intestine, lung, spleen and spinal cord) were taken out too: their labels don't say which animal they came from, and the same box held human slides.
  • Two specimens are poisonous plants (castor beans, oleander); their slides say so.

Where the slides come from

A box of 91 commercial teaching slides, scanned on an Aperio slide scanner. The web copies (276 MB) were white-balanced so empty glass reads white, cut into 512-pixel WebP tiles and packed into one PMTiles file per slide. The original scans of the 32 slides used (0.82 GB) are kept with the slide-label photos and the scanner's ID fields removed and every image tile byte-identical; the scans were made by X-WOW's owner, who chose CC0 1.0 for them on 11 October 2026; they wait in an unpublished Zenodo draft until the owner publishes it. One printed label in the box was wrong (a lily anther labelled as a rotifer); the game names what the tissue shows.

Checking the facts

Each postcard's fact is one or two plain sentences, written to be true and checkable; sizes come from the pixels. The facts and the game were made with AI, from the X-WOW owner's brief, and have not yet been checked by a person. If you spot a mistake, a grown-up can email info@x-wow.com and it gets fixed.

The game's code and text, and the slide images: CC0 1.0 (the images since 11 October 2026, the owner's decision). Built with OpenSeadragon (BSD-3-Clause), PMTiles (BSD-3-Clause) and fflate (MIT, inside PMTiles); their licences ship with the site.