Are short links case sensitive?
It depends on the service. The domain part of a link ignores capital letters, but the code after the slash may not. Some services treat Sale and sale as two different codes. Others treat them as the same.
Kort ignores case in its codes, and it treats O as 0 and I or L as 1. Make a link in the box below, then open it with the code in capitals to see.
Short answer: it depends on the service
A short link has two parts. The domain, such as kort.my, ignores case, so KORT.MY/ab opens the same site as kort.my/ab. The code after the slash is different. Each service decides whether Sale and sale are the same code.
Some services keep case, so Sale and sale are two codes. That fits more codes into each length, but a link typed in the wrong case fails. Other services ignore case, so a wrong capital still works. You can't tell which kind you have from the link alone.
Kort ignores case. kort.my/SALE, kort.my/sale and kort.my/sa1e all open the same link.
Other services set their own rules, and they can change them. For one example, the is.gd FAQ says its custom codes are case sensitive (read on 12 Oct 2026). For any other service, test a link, as shown next.
How to test any short link in a minute
- Open the short link and check that it works.
- In the address bar, change the case of the letters after the last slash. Turn ab into AB, or Ab into aB. Leave the domain alone.
- Press Enter.
- If the same page opens, the service ignores case for that code. If you see an error or a different page, it is case sensitive.
Test with a code that has at least one letter in it. A code made only of numbers has no case to change.
When you are not sure, copy and paste the link instead of typing it. That works on every service.
The other problem: lookalike characters
Capital letters are not the only way a typed link goes wrong. Some characters look alike, especially in print and in some fonts: the letter O and the number 0, and the capital I, the small l and the number 1.
Kort counts O as 0, and I and L as 1. So kort.my/o1 and kort.my/01 open the same link.
That leaves 33 symbols for codes: a to z and 0 to 9, without o, i and l. No two Kort codes can differ only by one of these lookalikes, so mixing them up can't send anyone to the wrong link.
What ignoring case costs
Fewer symbols means fewer codes of each length. This table compares Kort's 33 symbols with a service that counts small letters, capitals and numbers as different characters, which gives 62 symbols.
| Code length | Kort codes | With capitals counted separately |
|---|---|---|
| 2 characters | 1,089 | 3,844 |
| 3 characters | 35,937 | 238,328 |
| 4 characters | 1,185,921 | 14,776,336 |
| 5 characters | 39,135,393 | 916,132,832 |
Kort chose easy typing over the most codes. Random links are 5 characters long, which still gives 39,135,393 codes. The shortest codes are rented for a short time so that everyone gets a turn. For how that works, see Related pages below.
Where ignoring case helps
- Saying a link out loud. Nobody has to say capital S.
- Printing a link on paper, where people type it from the page.
- Typing on a phone, where the keyboard may change the case of the first letter.
- Reading a link in a font where I, l and 1 look the same.
This applies to Kort codes only. The long link you paste is a different matter. Kort sends visitors to the address you gave, tidied to a standard form. The website at that address decides whether its own page names need the right case. Paste the long link exactly as you copied it.
Common questions
Are short links case sensitive?
It depends on the service. The domain name ignores case, but the code after the slash is up to the service. Some treat Sale and sale as two codes, and some treat them as one. To find out, change the capitals in a link that works and open it.
Are Kort links case sensitive?
No. Kort ignores upper and lower case in its codes, so kort.my/SALE and kort.my/sale open the same link. That holds for random links, codes you choose and short rented codes.
Does Kort treat 0 and O the same?
Yes. O counts as 0, so kort.my/SHOP and kort.my/sh0p open the same link. I and L count as 1 in the same way.
How can I check if a short link is case sensitive?
Change the case of the letters after the last slash in the address bar, then press Enter. If the link breaks or opens a different page, it is case sensitive. The test needs a code with at least one letter in it.
Are Bitly and TinyURL links case sensitive?
We have not confirmed either service's rule from its own pages, so we won't guess. Run the one-minute test on this page with one of your own links. Services can change their rules, so test again if a link ever fails.
Why do some services use capital letters in codes?
Capitals give more codes of the same length. With small letters, capitals and numbers, a 5-character code has 916,132,832 possible values. Kort has 39,135,393 at that length. It gives up some codes so that a mistake in case, or a mix-up between O and 0, still opens the right link.