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Check a NACHA ACH file for structure errors

Upload an ACH or TXT file. It checks that every record is 94 characters and that header and control records are in place, without showing account numbers. Totals are not recalculated.

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ACH, TXT · Up to 100,000 entries
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Standard toolIncluded · 3 free jobs a dayFree: 3 jobs a dayPro: up to 200 jobs a day · €12.99/month or €89.99/year
  • ACH / TXT
  • Up to 100,000 entries
Prepared result preview · fictional sample dataFictional NACHA Fixed-Width Structure Preflight fixture
Source
1 prepared source file · 190 bytes
Prioritized findings
  • Records: 2
  • Record types: 6 recorded
  • Redacted: true

record-summary.json · findings.csv · manifest.json

BringACH, TXT
GetRecord-type summary, structural findings and manifest
PrivacyEncrypted source · 24-hour result

One clear job, from source to download

  1. 1

    Add the source

    Supported formats and limits are visible before the upload.

  2. 2

    Confirm the settings

    Review the exact source, options, units and access before processing.

  3. 3

    Inspect and download

    Check the preview and warnings, then unlock the complete package.

Checking the structure of a NACHA ACH file before upload

What you upload

You upload an ACH file as .ach or .txt, with up to 100,000 entry records per job. The check looks at the layout only. Every record must be 94 characters long, and the file header and file control records must sit where the format expects them. It also counts how many records of each type the file holds.

What comes back

The download holds record-summary.json, findings.csv and manifest.json. The summary and findings report record types, positions and counts. Account numbers are hidden throughout, which is why the preview shows a redacted flag. manifest.json records which file was read and sums up the run. Open findings.csv and fix each listed record before you run the file again.

What your bank still checks

There are no options to set. Batch totals and file control totals are not recalculated, and no routing or account number is checked. This is not NACHA certification. A file can look clean here and still be turned down by your bank. Use it as a first look before you submit, and let your bank's own checks give the final answer.

Questions before you run it

What does this preflight actually check?

Record length against the fixed 94-character layout, how many records of each type the file holds, and whether the file header and file control records sit where the format expects them.

Does it recompute batch and file control totals?

No. Entry hashes, batch totals and file control figures are not recalculated. The pass is structural, so a file can look clean here and still be rejected by the originating bank.

Are account numbers exposed anywhere in the result?

No. The record summary and findings report record types, positions and counts with account values redacted, which is why the preview carries a redacted flag.

Does a clean result mean my bank will accept the file?

No. This is not NACHA certification and it validates no routing or account number against any directory. Use it as a first look before a real submission, not as sign-off.

How large an ACH file can I run through it?

Up to 100,000 entry records, supplied as .ach or .txt. The package is record-summary.json, findings.csv and manifest.json.