IBAN Calculator

Calculate IBAN from bank code and account number

'+window._iban+'
'+details+''; let f=document.getElementById('ig-print-frame'); if(f)f.parentNode.removeChild(f); f=document.createElement('iframe'); f.id='ig-print-frame'; f.setAttribute('style','position:fixed;right:0;bottom:0;width:0;height:0;border:0;'); document.body.appendChild(f); let printed=false; const go=function(){ if(printed)return; printed=true; try{ f.contentWindow.focus(); f.contentWindow.print(); }catch(err){ try{window.print();}catch(e){} } }; f.onload=function(){ setTimeout(go,250); }; const d=f.contentWindow.document; d.open(); d.write(html); d.close(); setTimeout(go,600); // fallback: some browsers don't fire onload for document.write } }); // ─── GENERATE ──────────────────────────────────────────────────────────────── document.getElementById('ig-generate').addEventListener('click',()=>{ hideAlert();hideResult(); const code=sel.value; if(!code){showAlert('Please select a country.');return;} const c=C[code]; const vals={}; const errors=[]; c.fields.filter(f=>!f.auto).forEach(f=>{ const inp=document.getElementById('ig-f-'+f.id); let val=inp.value.toUpperCase().replace(/[^A-Z0-9]/g,''); if(!val){ if(f.optional){return;} else{errors.push('"'+f.l.replace(/ [ —\(].*/,'').trim()+'" is required.');inp.className='err';setIcon(inp,'err');return;} } if(f.n&&/[^0-9]/.test(val)){errors.push('"'+f.l.replace(/ [ —\(].*/,'').trim()+'" must be numeric.');inp.className='err';setIcon(inp,'err');return;} if(f.a&&!f.bic&&/[^A-Z]/.test(val)){errors.push('"'+f.l.replace(/ [ —\(].*/,'').trim()+'" must be letters only.');inp.className='err';setIcon(inp,'err');return;} // ── BIC fields ────────────────────────────────────────────────────────── if(f.bic){ if(val.length===8||val.length===11){ if(!/^[A-Z]{4}[A-Z]{2}[A-Z0-9]{2}([A-Z0-9]{3})?$/.test(val)){ errors.push('"'+f.l.replace(/ [ —\(].*/,'').trim()+'" is not a valid BIC code.');inp.className='err';setIcon(inp,'err');return; } val=val.substring(0,4); } else if(val.length!==4||/[^A-Z]/.test(val)){ errors.push('"'+f.l.replace(/ [ —\(].*/,'').trim()+'" must be 4 letters or a valid 8/11-character BIC.');inp.className='err';setIcon(inp,'err');return; } inp.value=val;inp.className='ok';setIcon(inp,'ok');vals[f.id]=val;return; } if(val.length>f.len){errors.push('"'+f.l.replace(/ [ —\(].*/,'').trim()+'" exceeds '+f.len+' characters.');inp.className='err';setIcon(inp,'err');return;} // FR/MC: account can be < 11 chars (zero-padded left) — pad before min check if((code==='FR'||code==='MC')&&f.id==='account'&&val.length<11) val=val.padStart(11,'0'); const canPadLeft=(f.n||(f.id==='account'))&&f.id!=='nib'&&f.id!=='nrb'&&!f.exact; const minLen=f.min||(canPadLeft?1:f.len); if(val.length=1&&day<=31?'Personal kennitala is not valid — check day, month and century digit.' :day>=41&&day<=71?'Company kennitala is not valid — check day+40, month and century digit.' :'Kennitala is not valid — must be 10 digits in personal (DDMMYY…) or company (DD+40MMYY…) format.'; errors.push(msg);inp.className='err';setIcon(inp,'err');return; } } const padded=f.flex?val:(canPadLeft?val.padStart(f.len,'0'):val); inp.value=padded; inp.className='ok';setIcon(inp,'ok'); vals[f.id]=padded; }); if(errors.length){showAlert(errors[0]);return;} // ── API CALL ────────────────────────────────────────────────────────────── const btn=document.getElementById('ig-generate'); btn.disabled=true;btn.className='ig-btn ig-btn-gen loading';btn.textContent='Calculating…'; const p={country:code}; if(vals.nrb){ // PL: full 26-digit NRB sent as account p.account=vals.nrb; } else if(vals.nib){ // PT: NIB → bankcode(4) + branch(4) + account(11) + cd(2) p.bankcode=vals.nib.substring(0,4); p.branch =vals.nib.substring(4,8); p.account =vals.nib.substring(8,19).padStart(11,'0'); if(vals.nib.length>=21) p.cd=vals.nib.substring(19); } else if(vals.tilinumero){ // FI: tilinumero → prefix(6) + zero-padded account(8) p.account=vals.tilinumero.substring(0,6)+vals.tilinumero.substring(6).padStart(8,'0'); } else if(vals.domestic){ if(code==='BE'){ // BE: 12-digit → bankcode(3) + account(7) + cd(2) p.bankcode=vals.domestic.substring(0,3); p.account =vals.domestic.substring(3,10); p.cd =vals.domestic.substring(10); } else if(code==='ES'){ // ES: CCC 20-digit → bankcode(4) + branch(4) + cd(2) + account(10) p.bankcode=vals.domestic.substring(0,4); p.branch =vals.domestic.substring(4,8); p.cd =vals.domestic.substring(8,10); p.account =vals.domestic.substring(10); } else { // BA, RS, MK, TN, MA — send full domestic number as account p.account=vals.domestic; } } else { // All standard countries: map named fields to API params const bc=vals.bank||vals.bankbranch||vals.bik||vals.clearing||vals.sort; if(bc) p.bankcode=bc; if(code==='MT') { p.bankcode=vals.branch; } // MT: sort code field → bankcode param else if(vals.branch) { p.branch=vals.branch; } if(vals.prefix) p.prefix=vals.prefix; // CZ/SK if(vals.account) p.account=vals.account; if(vals.kennitala) p.kennitala=vals.kennitala; // IS if(vals.type){ if(code==='IS') p.acc_type=vals.type; // IS: separate acc_type param else p.account=(p.account||'')+vals.type; } if(vals.owner) p.account=(p.account||'')+vals.owner; if(code==='NO') { p.account=vals.bank+vals.account; delete p.bankcode; } // NO: bank+account combined if(code==='BR') { p.account=(vals.account||'')+(vals.type||'')+(vals.owner||''); } // BR: account+type+owner → account; branch sent separately } // FR/MC: strip clé RIB if included (>11 chars), then ensure account is exactly 11 chars if((code==='FR'||code==='MC')&&p.account){ if(p.account.length>11) p.account=p.account.substring(0,11); p.account=p.account.padStart(11,'0'); } // POST to calculator.php — handles API call + SEPA merge server-side p.ajax=1; const chk=f=>{ const v=(f+'').toLowerCase().trim(); return(v==='1'||v==='yes'||v==='y'||v==='true') ?'' :''; }; fetch('calculate-iban',{method:'POST',body:new URLSearchParams(p)}) .then(r=>r.json()) .then(data=>{ if(!data.iban){showAlert(data.error||data.message||'Could not calculate IBAN. Please check your inputs.');return;} const iban=data.iban; window._iban=iban; document.getElementById('ig-iban-val').textContent=iban; const bankFields=[ {key:'bank', label:'Bank', full:true}, {key:'bic', label:'BIC'}, {key:'branch', label:'Branch Name'}, {key:'address',label:'Address'}, {key:'city', label:'City'}, {key:'zip', label:'Postal code'}, {key:'country',label:'Country code'}, ]; let bankHTML='
Bank details
'; bankFields.forEach(f=>{ let val=data[f.key]; if(f.key==='country'&&(val===undefined||val===null||val==='')) val=iban.substring(0,2); const display=val!==undefined&&val!==null&&val!==''?val:'—'; bankHTML+=`
${f.label}
${display}
`; }); bankHTML+='
'; const sepaKeys=[ {key:'SEPA CREDIT TRANSFER', label:'SCT'}, {key:'SEPA CREDIT TRANSFER INSTANT', label:'SCI RT1'}, {key:'SCI_TIPS', label:'SCI TIPS'}, {key:'SEPA DIRECT DEBIT', label:'SDD Core'}, {key:'SEPA B2B', label:'SDD B2B'}, {key:'SEPA CARD CLEARING', label:'SCC'}, ].filter(s=>data[s.key]!==undefined); let sepaHTML=''; if(sepaKeys.length){ sepaHTML='
SEPA schemes
'; sepaKeys.forEach(s=>{ const v=(data[s.key]+'').toLowerCase().trim(); const ok=v==='1'||v==='yes'||v==='y'||v==='true'; sepaHTML+=`
${s.label}
`; }); sepaHTML+='
'; } document.getElementById('ig-result-details').innerHTML=bankHTML+sepaHTML; document.getElementById('ig-result').className='ig-result-card downloads show'; }) .catch(e=>showAlert('API error: '+e.message)) .finally(()=>{btn.disabled=false;btn.className='ig-btn ig-btn-gen';btn.textContent='Calculate IBAN';}); });
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This is because banks hide a fee in the exchange rate, which means that you will spend more on international money transfers than you should.
We recommend using Wise (formerly TransferWise) which is often cheaper. For example, a 500 USD to EUR transfer could be up to 70% cheaper with Wise versus select providers*.
*Comparison based on research conducted July - August 2025 (see here or more information)

  

The IBAN calculator is part of our IBAN SUITE service.

IBAN Calculator: convert your BBAN to IBAN

Choose a country, enter your domestic bank details and the calculator returns the matching IBAN. A few examples to try:

United Kingdom (UK)
Sort Code200415
Account Number38290008
Germany (DE)
Branch Code (BLZ)37040044
Account Number0532013000
France (FR)
Code Banque30002
Code Guichet00550
Numéro de Compte0000157841Z

Already know your IBAN? You can check an IBAN for correctness.

The IBAN Calculator is a special software developed to convert a domestic bank code and account number into an International Bank Account Number (IBAN).

This page will help you accurately convert your Basic Bank Account Number (BBAN) to the equivalent IBAN Number. Our software also uses a local country check-digit algorithm to verify the checksum and thus the validity of an IBAN code. Another important function our clients benefit from is finding the BIC code (the bank identifier managed by the SWIFT network) of the appropriate bank and branch.

By using our IBAN converter you will increase the success rate and security of your international bank wire transfers. Our website dynamically adjusts the input fields according to the country selected, and our calculation engine will accurately generate IBANs from almost any country's domestic account number and bank code. For some countries we also support local account-number validation and BBAN-to-IBAN conversion.

The ISO standards behind IBAN conversion

Converting a domestic account number into an IBAN follows a set of international standards, and our engine applies all of them:

ISO 13616

Defines the IBAN as an internationally formatted version of your domestic BBAN. SWIFT is its official Registration Authority, and each country's format is registered by its national central bank or standards body.

ISO 3166-1

Provides the two-letter country code at the start of every IBAN — for example GB, DE or FR.

ISO 7064 (MOD-97-10)

Generates the two check digits: letters become digits (A = 10 … Z = 35) and the number must leave a remainder of 1 when divided by 97. This lets a bank instantly catch a mistyped digit before a payment is sent.

ISO 9362

Defines the BIC (SWIFT code): 8 or 11 characters — a 4-character institution code, a 2-character country code, a 2-character location code and an optional 3-character branch code.

The BBAN-to-IBAN conversion process, step by step

Conversion is not a single calculation. Our engine runs several independent checks in sequence and reports each result separately, so a problem is traced to the exact stage where it occurs:

1
Identify the country and load its rules — which fields exist, their order, lengths and allowed characters. The input fields adjust dynamically to match.
2
Validate field format and length. Numeric fields that are too short are padded with leading zeros where the format allows; fixed-length fields are rejected if they don't match exactly.
3
Verify the bank code exists by looking it up in the national bank directory, retrieving the bank name, branch and address. An unknown code is flagged here.
4
Run the national (domestic) check digit. Many countries embed their own checksum inside the BBAN, with a country-specific algorithm — France uses a MOD-97 RIB key, Spain two control digits, Italy a CIN character, the Netherlands a MOD-11 test, and Germany methods that differ from bank to bank. The engine recomputes it to confirm the account number is internally consistent.
5
Assemble the BBAN in the exact positions and lengths defined by the country's ISO 13616 format.
6
Calculate the IBAN check digits. The country code and a temporary "00" move to the end, letters become numbers, and the two digits are derived with the ISO 7064 MOD-97-10 formula: 98 minus the remainder of that number divided by 97.
7
Validate the full IBAN structure against the country's registered template (length and character type at every position), with the MOD-97 test over the whole string leaving a remainder of 1.
8
Determine the BIC — the 8- or 11-character SWIFT code (ISO 9362) used to route the payment.
9
Return SEPA participation for euro accounts, so the bank's reachability is known before a payment is sent.
10
Output the result: the IBAN in electronic and print format, the BIC, the bank name, branch and address, and the SEPA scheme information.

Because each stage is independent, an IBAN can be structurally valid (step 7) while still failing the national check (step 4) if the original account number was mistyped — which is why our engine reports each result separately.

SEPA: what it is and what the calculator tells you

SEPA (the Single Euro Payments Area) lets euro payments between participating countries be made as easily and affordably as a domestic payment. It is built on the IBAN — and, where required, the BIC — which is why a correct IBAN is essential for any SEPA transfer. The main schemes are:

SEPA Credit Transfer
A standard one-off or recurring euro transfer, initiated by the payer.
SEPA Instant (SCT Inst)
The same, but funds arrive within seconds, 24/7.
SEPA Direct Debit — Core
Collections from consumer accounts, based on a signed mandate.
SEPA Direct Debit — B2B
The business-to-business version.
When you convert an account in a SEPA country, our engine returns the receiving bank's participation in these schemes — its reachability — so you can avoid payments that would be rejected because the bank doesn't support the scheme you intended to use. Note that a valid IBAN confirms only that the format and checksum are correct; it does not prove the account is open or reachable for every scheme. The SEPA participation result answers that.