IBAN Checker
Validate any IBAN with the official ISO 13616 MOD-97 checksum. Everything runs in your browser — nothing is sent or stored.
What this check does — and does not do
A valid checksum means the IBAN is correctly formed: no typos, right length for the country, valid MOD-97 remainder. It does not mean the bank account exists or belongs to a specific person — only a bank can confirm that.
IBAN length by country
Every country fixes its own IBAN length. If the character count does not match the table below, the IBAN is invalid before any math is applied — the most common cause is a missing or extra digit when copying by hand.
| Country | Len | Country | Len | Country | Len |
|---|---|---|---|---|---|
| Andorra (AD) | 24 | Austria (AT) | 20 | Belgium (BE) | 16 |
| Bulgaria (BG) | 22 | Switzerland (CH) | 21 | Cyprus (CY) | 28 |
| Czechia (CZ) | 24 | Germany (DE) | 22 | Denmark (DK) | 18 |
| Estonia (EE) | 20 | Spain (ES) | 24 | Finland (FI) | 18 |
| France (FR) | 27 | United Kingdom (GB) | 22 | Greece (GR) | 27 |
| Croatia (HR) | 21 | Hungary (HU) | 28 | Ireland (IE) | 22 |
| Iceland (IS) | 26 | Italy (IT) | 27 | Liechtenstein (LI) | 21 |
| Lithuania (LT) | 20 | Luxembourg (LU) | 20 | Latvia (LV) | 21 |
| Monaco (MC) | 27 | Malta (MT) | 31 | Netherlands (NL) | 18 |
| Norway (NO) | 15 | Poland (PL) | 28 | Portugal (PT) | 25 |
| Romania (RO) | 24 | Sweden (SE) | 24 | Slovenia (SI) | 19 |
| Slovakia (SK) | 24 | San Marino (SM) | 27 |
FAQ
Why did my payment bounce even though the IBAN is valid?
A checksum-valid IBAN can still point to a closed or non-existent account. Always verify the beneficiary through a second channel before large transfers.
Is it safe to type an IBAN here?
Yes — the validation runs entirely in your browser with JavaScript. The IBAN never leaves your device and is not stored anywhere.
How is the check digit computed?
Move the first four characters to the end, replace letters with numbers (A=10 … Z=35), and divide by 97: a valid IBAN leaves a remainder of exactly 1.
Format and checksum validation only (ISO 13616). This tool does not verify that the account exists.