A FINSTACKCLOUD TOOLKIT
The toolkit for payment file formats.
Inspect, validate, and convert NACHA, FedWire, SWIFT MT, ISO 20022, and X9.37 files — without uploading them anywhere. Built by engineers who actually ship payment integrations.
Parsed snapshot · sample file
File header
Type 1- Destination routing
- 123456780
- Origin routing
- 987654320
- Destination name
- Sample Receiving Bank
- Origin name
- Demo Originator Inc
- File creation
- 10/15/2025 · 09:00
Batches
- Vendor Alpha Inc CCD
2 entries · effective 10/16/2025
- Pension Demo LLC CCD
2 entries · effective 10/16/2025
- Northwind Supply PPD
1 entries · effective 10/16/2025
File control
Type 9- Batches
- 000003
- Entry rows
- 00000009
- Blocks
- 000002
Same pipeline as the tool — nothing uploaded. Open NACHA inspector →
PRODUCT
One toolkit. Every payment rail.
ACH moves $80 trillion a year. Wires move trillions more. The tools for working with their files mostly look like 2009. We're rebuilding them — one rail at a time.
ACH
Direct deposit, bill pay, B2B transfers — 30 billion ACH transactions clear every year, all through NACHA-formatted files. We parse and validate them with the rules that actually catch real returns.
Tools live: Parser · Validator
Tools coming: Generator · Diff · Returns Decoder
Wire (FedWire & SWIFT)
The hardest part of wire integration isn't sending the message — it's debugging why a SWIFT MT103 or ISO 20022 pacs.008 got rejected at 3 AM. We're building the tooling that explains it.
Tools coming: Parser · Validator · MT⇄MX Converter
FedNow (ISO 20022)
The Fed's instant payment rail uses the same ISO 20022 message family as SEPA and CBPR+. The good news: there's finally a standard. The bad news: pacs.008 has 200+ fields. We make sense of them.
Tools coming: Parser · Validator · Mock Generator
Check (X9.37)
Paper checks were supposed to die in 2010. They didn't. X9.37 image cash letters still move billions of dollars between banks every day, and the format is a nightmare.
Tools coming: Parser · Validator · Image Extractor
PRIVACY
Your files don't leave this browser tab.
Account numbers, routing numbers, names. SSN fragments. Everything that's in a NACHA file is exactly what you don't want sitting on some random server. So we built it differently.
100% browser-side
Files are read and parsed by JavaScript in your tab. They never touch our servers, our logs, or any third party. Open DevTools and verify for yourself.
Built on real specs, not Stack Overflow
The parsers implement NACHA Operating Rules, ISO 20022 schemas, and SWIFT message standards. We update them when the rules change. The error messages tell you which spec section was violated.
Fast where it matters
A 10MB NACHA file with 50,000 entries parses in under two seconds. No spinners. No upload progress bars. No "please wait, processing..."
Start with the NACHA Validator.
Drop in a file. See every record decoded. Get every error explained before your bank rejects it.
Free. No signup. No upload. Files stay local.