How this validator helps you

Test payment data against the checks banks apply — required fields, IBAN checksums, BIC structure, control totals
Generate a working pain.001.001.09 credit-transfer file you can inspect, copy, or download
Prove the result against the official ISO 20022 schema — the genuine XSD, validated in your browser

Important information

Nothing is uploaded. Your file is read by your own browser and never leaves your machine — there is no server, no storage, no telemetry. Safe for real data, though masked test data is always good practice.
Testing tool only. Files are never submitted for processing and no payments can result from anything you do here.
Expected columns: payment_id, payment_amount, currency, debtor and creditor name / IBAN / BIC, requested_execution_date — comma, semicolon, and tab delimiters are auto-detected. Download a sample below to use as a template for your own export.
No charges. This tool, and the full toolchain behind it, are free and open source.

Verify it yourself

"Nothing is uploaded" is a claim you can falsify in two minutes:

Open DevTools → Network, then use the demo. The only requests are same-origin GETs for this page's assets, the WASM engine, and the schema — none carries your data.
Run the XSD gate once, then switch DevTools to Offline (or turn off Wi-Fi). The whole demo — including the official schema gate — still works: a service worker caches everything after first use.
This page is open source too — the demo logic is one dependency-free module you can read in full.

There is no analytics script, no error-reporting service, no third-party font, and no CSP report endpoint — reporting would itself be an outbound connection.

Add your payment data

Drag a CSV file here — or click to browse

Maximum 2 MB · read locally by your browser, never uploaded

Download a sample to use as your own template: SEPA credit transfer · cross-border · 20-row batch

Validation result & generated XML

Add data in step 1 — validation runs automatically.

What was checked
ISO 20022 schema	—
Data quality (beyond the schema)	—
Scheme rulebook	Not run — choose a scheme rulebook in step 1
Your bank’s profile	Not evaluated — Pain001 ships no bank profiles
Channel and eligibility	Not evaluated — decided by your bank, not the file

Validation findings by row and column
Row	Column	Rule	Value	Problem

The validated pain.001.001.09 document will appear here — add data in step 1.

Prove it against the official ISO 20022 XSD

Steps 1–2 already ran the pain001 library itself: its record validation, the scheme rulebook you chose, XML generation, and the official pain.001.001.09 schema gate on the result, all inside a Python runtime compiled to WebAssembly and served from this site. This button re-runs the schema gate on the XML shown above, so you can edit the document and check it again. The runtime (about 28 MB) downloads once, the first time you validate, and stays cached.

Generate XML in step 2 first — the XSD gate runs on that output.

Everything on this page runs in your browser — nothing is uploaded, stored, or sent anywhere. It runs the pain001 library itself, the same package you install with pip, inside a Python runtime compiled to WebAssembly: record validation, IBAN and BIC checks, the scheme rulebook you choose, XML generation with recomputed NbOfTxs/CtrlSum control totals, and the official XSD gate. What the CLI adds is scale and inputs: files of any size, Excel, SQLite, JSON, Parquet and SWIFT MT101, and every message edition — install the CLI for the complete pipeline.

What this demo shows — and what the real pipeline adds

Each sample batch is also downloadable as a CSV file to use as the template for your own ERP or spreadsheet export — the header row is the contract.

The demo above implements the fail-fast layer of the Pain001 pipeline: required-field checks, ISO 13616 mod-97 IBAN checksums, ISO 9362 BIC structure, amount and date formats, and control totals (NbOfTxs, CtrlSum) recomputed from the records rather than trusted. Try the "Introduce an error…" menu — each scenario plants exactly one realistic flaw (a flipped IBAN digit, a malformed BIC, a missing column, a European comma-decimal amount, an impossible date) and shows you the row-level finding a bank's gateway would otherwise report days later.

The installed toolchain runs a much deeper gate: JSON Schema validation per record with field-alias normalisation, five scheme rulebooks (SEPA SCT, Instant, SDD Core, B2B, cross-border) with rule-by-rule --explain output, and final validation of the rendered document against the official ISO 20022 XSD before a single byte is written. Ten pain.001 versions and pain.008.001.02 are supported.

pip install pain001
pain001 -t pain.001.001.09 -d payments.csv -o out/ --scheme sepa-sct --dry-run

Step 3 above is not a simulation: it boots a Python runtime in WebAssembly and runs xmlschema against the official pain.001.001.09 schema, served from this site — the same class of XSD gate the CLI applies. What remains CLI-only is the rest of the pipeline: JSON Schema normalisation, the five scheme rulebooks with --explain, and the other ten message definitions.