Synthetic 837 Test File Generator
Generate complete, structurally valid X12 837P, 837I, and 837D claim files with payer-specific envelopes — synthetic patients, checksum-valid fake NPIs, and fictional charges, ready for clearinghouse certification and pipeline testing. Download as .edi in one click. Free, no signup, nothing stored.
Test environments only. Every claim is synthetic — never submit generated files to production payers or any HIPAA-covered transaction.
Generated in your browser — nothing is sent to or stored on our servers.
A complete, balanced 837 — not a snippet
Each file is a full production-shaped transmission, so your parsers, validators, and balancing logic see exactly what a real clearinghouse file looks like:
- ISA/GS/GE/IEA envelopes with payer-specific receiver IDs and correct fixed-width ISA padding
- Versioned ST/SE per transaction: X222A1 (837P), X223A2 (837I), X224A2 (837D)
- HL hierarchy: billing provider → subscriber → claim, with NM1*85/IL/PR loops
- CLM totals always equal the sum of SV1/SV2/SV3 line charges — balancing passes
- Synthetic patients with never-issued identifiers; NPIs pass the CMS Luhn checksum
- Optional payer-mandated segments: prior authorization (REF*G1) and rendering provider (NM1*82)
ISA*00* *00* *ZZ*HEWTOTEST *ZZ*87726 *250929*1200*^*00501 *000000001*0*T*:~ GS*HP*HEWTOTEST*87726*20250929*1200*1*X *005010X222A1~ ST*837*0001*005010X222A1~ BHT*0019*00*012345*20250929*1200*CH~ ... CLM*SYNTH00001*500***11:B:1*Y*A*Y*I~ HI*ABK:E119~ LX*1~ SV1*HC:99213*150*UN*1***1~ DTP*472*D8*20250915~ ... SE*24*0001~ GE*1*1~ IEA*1*000000001~
Pair with the Fake NPI Generator and Fake Patient Generator for fully custom test data, or convert real paper claims to 837 with Hewto.ai's Paper to EDI service.
Production-shaped test claims, zero PHI
Clearinghouse certification
Rehearse Availity, Waystar, or Change Healthcare test-mode submissions with payer-shaped envelopes before your first real file.
Pipeline & parser QA
Exercise ISA/GS handling, loop parsing, claim balancing, and SE segment counting against structurally valid files — 837P, I, and D.
Training & demos
Teach EDI analysts and demo RCM workflows on realistic 837 files with zero protected health information anywhere in the loop.
Envelope IDs are the commonly published payer identifiers for each payer — always confirm against the payer's current companion guide before certification testing. Generated files are synthetic and carry no real member, provider, or claim data.
Common questions about 837 test files
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