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Croatia IBAN Validator
Validates a Croatian IBAN: the mod-97 checksum, the 21-character length and the structure, with the bank code identified.
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In short
A Croatian IBAN is exactly 21 characters: HR, two check digits, then 7 digits, then 10 digits — so the 7 characters after the check digits are the bank code — 1001005 in the example — and the remaining 10 are the account number, 1863000160. Croatia’s seven-digit bank code is unusually long, and it is followed by ten digits of account for a twenty-one character IBAN. The checksum is ISO 7064 MOD-97-10: move the first four characters to the end, turn each letter into its position in the alphabet plus nine, and read the result as one long number, which must leave remainder 1 when divided by 97. That catches every single-character mistake and almost every swap of two neighbouring characters, which is what it was designed for and why an IBAN is worth checking before you pay rather than after. What it cannot do is tell you the account exists, is open, or belongs to the person you think — a random string of the right shape passes about once in 97 tries, and no amount of arithmetic reaches into a bank. This page runs entirely in your browser, so the number you type is not sent anywhere.
How to use the Croatia IBAN Validator
- Paste the Croatian IBAN — spaces and dashes are fine.
- Read the three checks: mod-97, length and structure.
- If it fails, the page says which check failed and what that usually means.
About the Croatia IBAN Validator
Checks a Croatian IBAN three ways — checksum, length and structure — and says which of the three failed when one does, because they mean different things.
What people use it for
- Checking a Croatian IBAN before sending money to it.
- Finding the bank code inside an IBAN you have been given.
- Confirming a Croatian number was typed or pasted correctly.
Details
| Length | 21 characters, always |
|---|---|
| Structure | 7!n10!n after the check digits |
| In words | HR, 2 check digits, then 7 digits, then 10 digits |
| Bank code | 7 characters — 1001005 in the example |
| Example | HR12 1001 0051 8630 0016 0 |
| Check digits | Always between 02 and 98. 00, 01 and 99 cannot occur |
| Privacy | The arithmetic runs in your browser. Nothing you type is sent anywhere |
The maths behind it
This tool uses ISO 7064 MOD-97-10 — move the first four characters to the end, replace each letter with its position plus nine, and a valid IBAN leaves remainder 1 on division by 97. On top of that, Croatian IBANs are exactly 21 characters and follow 7!n10!n. Every intermediate value is shown on screen, so the result can be checked by hand.
Three checks, reported separately on purpose. A length error means a character is missing or extra, a structure error means a letter sits where a digit belongs, and a checksum failure with both of those right means a genuine typo inside the number — most often two neighbouring characters swapped.
Where this tool stops
It checks arithmetic and shape. It cannot tell you the account exists or who it belongs to, it does not look the bank up, and it does not verify any national check digits Croatia may use inside its own account number — those are separate rules, computed differently, and passing mod-97 says nothing about them.
Frequently asked questions
How many characters is a Croatian IBAN?
Exactly 21, with no exceptions. After the two check digits the structure is 7!n10!n — 7 digits, then 10 digits. A number of any other length is not a Croatian IBAN, whatever else about it looks right.
Why is the Croatian bank code seven digits?
It carries the bank and its office in one number rather than splitting them, which is why this page shows a seven-digit bank identifier and no separate branch.
Where is the bank code in a Croatian IBAN?
The 7 characters after the check digits are the bank code — 1001005 in the example — and the remaining 10 are the account number, 1863000160.
Does a valid checksum mean the account exists?
No, and this is the thing worth taking away. Mod-97 proves the number is internally consistent — that it was probably typed correctly. It says nothing about whether the account is open, or whose it is. A random string of the right length passes about once in every 97 attempts. Only the bank can confirm the rest.
Is it safe to paste an IBAN here?
The checking happens in your browser and the number is never sent to a server — there is no request to make one. An IBAN is not a secret the way a card number is, since it is printed on every invoice you send, but it is still yours, and it does not leave your machine here.
Is there a limit on how often I can use the Croatia IBAN Validator?
It is free, with no account, no trial and no daily cap. Every security tool on inputtesthub.com works the same way: open the page and use it.
Is my data uploaded anywhere?
No. The Croatia IBAN Validator runs entirely in your browser using JavaScript. Nothing is transmitted, logged or stored, which you can verify yourself in the Network tab of your browser's developer tools.
What is the equation behind the Croatia IBAN Validator?
It uses ISO 7064 MOD-97-10 — move the first four characters to the end, replace each letter with its position plus nine, and a valid IBAN leaves remainder 1 on division by 97. On top of that, Croatian IBANs are exactly 21 characters and follow 7!n10!n. The full working is printed under the result, so you can follow every step rather than trusting a black box.
When would I actually need the Croatia IBAN Validator?
The most common reasons people reach for it: checking a Croatian IBAN before sending money to it. Finding the bank code inside an IBAN you have been given. Confirming a Croatian number was typed or pasted correctly. It is built for exactly those cases rather than being a general-purpose tool with this bolted on.
When is the Croatia IBAN Validator not the right tool?
It checks arithmetic and shape. It cannot tell you the account exists or who it belongs to, it does not look the bank up, and it does not verify any national check digits Croatia may use inside its own account number — those are separate rules, computed differently, and passing mod-97 says nothing about them. Knowing where a tool stops being trustworthy matters more than the cases where it works.
Which values should I know?
Length is 21 characters, always. Structure is 7!n10!n after the check digits. In words is HR, 2 check digits, then 7 digits, then 10 digits. These are printed on the page itself, so you do not have to take them on trust.
Does the Croatia IBAN Validator work on a phone?
Yes. The page is responsive and the tool works in Chrome, Safari, Firefox, Edge and Samsung Internet on both Android and iOS. There is no app to install and nothing to sign into.
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