Skip to main content
A Random Link is one whose slug QRtub picks: six lowercase letters, resolving at qrtub.com/{slug}. You cannot choose the slug, and there is nothing to configure — which is exactly why it is the default and the fastest way to get printable codes.

​
How the slug is generated

Six letters from a to z, like qrtub.com/bepjov. No digits, no capitals, no punctuation. That is 26⁶ — a little over 308 million addresses. The length and the alphabet are fixed. There is no setting for a longer slug, a shorter one, or a different character set anywhere in QRtub — if you send a request asking for one, it is ignored and the standard six-letter slug is minted instead. Two random slugs can never clash. QRtub does not draw at random and check whether the result is free; it derives each name from a counter through a cipher, and a cipher is a one-to-one mapping. Two Links cannot arrive at the same name, so creating five hundred at once never asks you to resolve a conflict. A random slug can never clash with a numbered one either. Numbered slugs always contain digits and random ones never do, so the two shapes cannot meet. The one case that is possible is a custom slug that happens to look like a random one — bepjov is a legal custom slug. QRtub handles it without telling you: the database refuses the duplicate and the mint retries with new names. You will not see an error, and you cannot end up with two Links on one address.

​
Creating them

On the Links page, open the create form and choose Random as the strategy. Set Number of Links — the form accepts up to 100 in one request — and create. Each Link comes into existence unattached: a real, resolvable address with no Item, no Page and no destination until you give it one. Random is also the type QRtub uses when a Collection is set to mint a Link automatically for each new Item. That is a Collection-level setting rather than a property of the Link itself.

​
Case does not matter

qrtub.com/bepjov and QRTUB.COM/BEPJOV resolve to the same Link, as do numbered and custom slugs. How a code is printed is a typography decision, not a correctness one — set it in capitals on a plate if that reads better at distance. QRtub writes the address in lowercase everywhere it displays one, so that is the form you will see in the app and in an export.