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Poland IBAN Validator

Validates a Polish IBAN: the mod-97 checksum, the 28-character length and the structure, with the national clearing number identified.

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In short A Polish IBAN is exactly 28 characters: PL, two check digits, then 8 digits, then 16 digits — so the 8 characters after the check digits are the national clearing number — 10901014 in the example — and the remaining 16 are the account number, 0000071219812874. Poland’s eight digits carry the bank and its branch together as one national clearing number, and the last of those eight is a check digit on the seven before it. The sixteen digits after are the account. 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 Poland IBAN Validator

  1. Paste the Polish IBAN — spaces and dashes are fine.
  2. Read the three checks: mod-97, length and structure.
  3. If it fails, the page says which check failed and what that usually means.

About the Poland IBAN Validator

Checks a Polish 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 Polish IBAN before sending money to it.
  • Finding the national clearing number inside an IBAN you have been given.
  • Confirming a Polish number was typed or pasted correctly.

Details

Length28 characters, always
Structure8!n16!n after the check digits
In wordsPL, 2 check digits, then 8 digits, then 16 digits
National clearing number8 characters — 10901014 in the example
ExamplePL61 1090 1014 0000 0712 1981 2874
Check digitsAlways between 02 and 98. 00, 01 and 99 cannot occur
PrivacyThe 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, Polish IBANs are exactly 28 characters and follow 8!n16!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 Poland 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 Polish IBAN?
Exactly 28, with no exceptions. After the two check digits the structure is 8!n16!n — 8 digits, then 16 digits. A number of any other length is not a Polish IBAN, whatever else about it looks right.
Is the Polish bank code eight digits or four?
Eight, and they are not divisible into a separate bank and branch the way France’s ten are. Poland issues one clearing number per branch, so this page shows all eight as the bank identifier rather than inventing a split.
Where is the bank code in a Polish IBAN?
The 8 characters after the check digits are the national clearing number — 10901014 in the example — and the remaining 16 are the account number, 0000071219812874.
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 Poland 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.
Can you see what I put into this utility?
No. The Poland 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 Poland 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, Polish IBANs are exactly 28 characters and follow 8!n16!n. The full working is printed under the result, so you can follow every step rather than trusting a black box.
What do people use the Poland IBAN Validator for most?
The most common reasons people reach for it: checking a Polish IBAN before sending money to it. Finding the national clearing number inside an IBAN you have been given. Confirming a Polish number was typed or pasted correctly. It is built for exactly those cases rather than being a general-purpose tool with this bolted on.
Where does the Poland IBAN Validator stop being reliable?
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 Poland 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.
What are the key numbers for the Poland IBAN Validator?
Length is 28 characters, always. Structure is 8!n16!n after the check digits. In words is PL, 2 check digits, then 8 digits, then 16 digits. These are printed on the page itself, so you do not have to take them on trust.
Is there an app version?
Yes. The page is responsive and the utility 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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