Drop an X12 837 claim file, professional or institutional, and it runs the rule library below before the claim ever reaches a payer. Drop an 835 remittance instead and it reads the claim adjustment reason codes to show which denials were preventable, and which scrub rule would have caught each one.
An 837 contains PHI. Everything runs locally in your browser. No file is uploaded, transmitted, or stored, and nothing persists when you close the tab. On a shared or public device, use de-identified test files only.
Where these rules come from. This engine is original work built on published US standards: the X12 837P and 837I implementation guides, the CMS National Correct Coding Initiative, the CMS Claims Processing Manual, AMA CPT conventions, ICD-10-CM guidelines, and 42 CFR. Every rule cites the public source it rests on. It does not reproduce any payer's proprietary edit list. Rules that need a CMS reference file, a fee schedule indicator, or claim history are shown as inactive rather than guessing.
1 · Load a file
Drop 837 or 835 files here
Format detected automatically. Professional (837P) and institutional (837I) both supported
0
Files
0
Claims
0
Service lines
0
Errors
0
Warnings
0
Advisories
0
Clean claims
Scrub findings
Errors will very likely reject or deny. Warnings are payer-dependent and worth a look. Advisories are judgment calls.
Denial pattern analysis (835)
Adjustment reason codes ranked by dollars withheld. The right column maps each reason to the scrub rule that would have caught it upstream.
Amounts reflect CAS adjustment amounts, not the full billed charge. Reason code meanings are summarized in plain language, not reproduced from the X12 code list.
Rule library
Every rule this tool runs
Each rule cites the public standard it rests on, so you can defend it in a payer conversation. Toggle any rule off and reload a file to rerun.
Educational tool, not billing or legal advice. Rules reflect commonly published US standards and payer conventions; specific requirements vary by payer, plan, state, and contract. Always validate against your clearinghouse edits and payer companion guides before submission.
(c) 2026 Merwin David · All rights reserved · Unauthorized copying prohibited