A QR code built from Emoji

It's possible to encode QR images as text. In this case, Emoji!

⬜️⬜️⬜️⬜️⬜️⬜️⬜️⬜️⬜️⬜️⬜️⬜️⬜️⬜️⬜️⬜️⬜️⬜️⬜️⬜️⬜️⬜️⬜️
⬜️⬛️⬛️⬛️⬛️⬛️⬛️⬛️⬜️⬜️⬜️⬛️⬜️⬜️⬜️⬛️⬛️⬛️⬛️⬛️⬛️⬛️⬜️
⬜️⬛️⬜️⬜️⬜️⬜️⬜️⬛️⬜️⬛️⬛️⬜️⬛️⬛️⬜️⬛️⬜️⬜️⬜️⬜️⬜️⬛️⬜️
⬜️⬛️⬜️⬛️⬛️⬛️⬜️⬛️⬜️⬜️⬛️⬜️⬛️⬛️⬜️⬛️⬜️⬛️⬛️⬛️⬜️⬛️⬜️
⬜️⬛️⬜️⬛️⬛️⬛️⬜️⬛️⬜️⬛️⬛️⬜️⬛️⬛️⬜️⬛️⬜️⬛️⬛️⬛️⬜️⬛️⬜️
⬜️⬛️⬜️⬛️⬛️⬛️⬜️⬛️⬜️⬜️⬜️⬛️⬜️⬜️⬜️⬛️⬜️⬛️⬛️⬛️⬜️⬛️⬜️
⬜️⬛️⬜️⬜️⬜️⬜️⬜️⬛️⬜️⬛️⬛️⬛️⬛️⬛️⬜️⬛️⬜️⬜️⬜️⬜️⬜️⬛️⬜️
⬜️⬛️⬛️⬛️⬛️⬛️⬛️⬛️⬜️⬛️⬜️⬛️⬜️⬛️⬜️⬛️⬛️⬛️⬛️⬛️⬛️⬛️⬜️
⬜️⬜️⬜️⬜️⬜️⬜️⬜️⬜️⬜️⬜️⬜️⬛️⬜️⬛️⬜️⬜️⬜️⬜️⬜️⬜️⬜️⬜️⬜️
⬜️⬛️⬛️⬛️⬛️⬛️⬜️⬛️⬛️⬛️⬛️⬜️⬛️⬛️⬛️⬜️⬛️⬜️⬛️⬜️⬛️⬜️⬜️
⬜️⬜️⬜️⬜️⬜️⬜️⬜️⬜️⬛️⬛️⬛️⬛️⬛️⬜️⬛️⬜️⬛️⬛️⬛️⬛️⬛️⬛️⬜️
⬜️⬛️⬛️⬜️⬜️⬜️⬜️⬛️⬛️⬜️⬜️⬛️⬛️⬛️⬛️⬜️⬜️⬜️⬜️⬛️⬛️⬜️⬜️
⬜️⬛️⬜️⬜️⬜️⬜️⬛️⬜️⬜️⬛️⬛️⬜️⬜️⬜️⬛️⬜️⬜️⬛️⬛️⬛️⬜️⬜️⬜️
⬜️⬜️⬛️⬜️⬛️⬛️⬛️⬛️⬛️⬛️⬛️⬛️⬛️⬜️⬜️⬛️⬜️⬛️⬛️⬜️⬜️⬛️⬜️
⬜️⬜️⬜️⬜️⬜️⬜️⬜️⬜️⬜️⬛️⬛️⬜️⬜️⬜️⬛️⬜️⬛️⬛️⬛️⬛️⬜️⬛️⬜️
⬜️⬛️⬛️⬛️⬛️⬛️⬛️⬛️⬜️⬛️⬜️⬜️⬜️⬛️⬜️⬜️⬛️⬜️⬜️⬛️⬛️⬜️⬜️
⬜️⬛️⬜️⬜️⬜️⬜️⬜️⬛️⬜️⬜️⬛️⬛️⬜️⬛️⬛️⬜️⬜️⬛️⬛️⬛️⬜️⬜️⬜️
⬜️⬛️⬜️⬛️⬛️⬛️⬜️⬛️⬜️⬛️⬛️⬛️⬛️⬛️⬜️⬛️⬜️⬛️⬛️⬜️⬜️⬜️⬜️
⬜️⬛️⬜️⬛️⬛️⬛️⬜️⬛️⬜️⬛️⬜️⬜️⬛️⬜️⬛️⬜️⬛️⬛️⬜️⬛️⬛️⬜️⬜️
⬜️⬛️⬜️⬛️⬛️⬛️⬜️⬛️⬜️⬛️⬜️⬜️⬛️⬛️⬛️⬜️⬛️⬜️⬜️⬛️⬜️⬜️⬜️
⬜️⬛️⬜️⬜️⬜️⬜️⬜️⬛️⬜️⬛️⬛️⬜️⬜️⬜️⬛️⬜️⬛️⬛️⬜️⬛️⬜️⬜️⬜️
⬜️⬛️⬛️⬛️⬛️⬛️⬛️⬛️⬜️⬛️⬛️⬜️⬛️⬜️⬜️⬛️⬛️⬛️⬛️⬜️⬛️⬜️⬜️
⬜️⬜️⬜️⬜️⬜️⬜️⬜️⬜️⬜️⬜️⬜️⬜️⬜️⬜️⬜️⬜️⬜️⬜️⬜️⬜️⬜️⬜️⬜️

How?

There are lots of ASCII block characters, but none are specifically marked as white / empty. Additionally, some fonts don't make the characters pure squares.

There are two characters which, generally, render as square Emoji:

• Unicode character U+2B1B is a large black square ⬛ .
• Unicode character U+2B1C is a large white square ⬜ .

These characters are from the Unicode block "Geometric Shapes". When paired with ️Variation Selector-16, they are given an Emoji presentation.

The above QR code is styled with "line-height:1em;" to make sure there are no vertical gaps between characters, and "letter-spacing:-3px;" to squash any horizontal gaps.

I found that it scanned reliably on my devices.

Why?

I was having a discussion with someone about the limitations of text based communication. How do you send a QR in, say, an email when you aren't allowed to attach anything? We were looking at a text only system which wouldn't allow attachments or BASE64 encoded inline.

So I knocked up a quick scrap of code to see if it would work with Emoji. It sort of works - but only if you can control the exact layout. On mobile screens, it might be too narrow, and you can't easily control the character spacing.

So, a nice idea, but a little pointless!

Can I tweet that??!?

The smallest possible QR code is 21x21 pixels, that's too many characters to fit into a Tweet. Sorry!

You can post it on something like Mastodon but without the fine-grained CSS control, it probably won't be readable.