Stop guessing why your HL7 message broke.
Find the offending segment in seconds, not hours.
A desktop tool built by HL7 engineers, for HL7 engineers. Paste an ORM, ORU, ADT, SIU, DFT — any v2.x message — pick a rule, hit Run. See exactly which segment is wrong, where, and why. No CLI, no curl scripts, no chasing whitespace through Notepad++.
Free for everyone with a Neureau account. No credit card.
The problem you actually have
You've stared at this before.
A vendor's interface engine spat out an ORM^O01 that "validates" against the spec — except your
downstream system rejects it with a generic 400. You open the message in a text editor and start
counting pipes. Is it MSH|^~\&|... or MSH|^~\&|? Is the IN3
segment in the wrong group? Did the EHR add a stray ZAL that nobody documented? You spend forty
minutes finding one missing required segment.
Or: a partner sends a "valid" SIU^S12 and your validator says fifteen things are wrong — but actually only one segment is misplaced, and the rest is a cascade of bogus errors caused by that one offender. Now you have to triage which errors are real.
This is the work HL7 integration teams do every day. The tooling for it hasn't changed in a decade.
What Neureau HL7 Validator does
A focused, fast, opinionated tool for the specific problem of structural HL7 v2.x message validation. It runs locally on your laptop. Your messages never leave your machine.
Precision over noise
Follow-set-aware error recovery isolates the actual offending segment, reports it once with a precise explanation, and keeps validating the rest of the message as if it weren't there. You stop chasing ghosts.
Live syntax coloring
Segment names in dark blue, field separators in muted grey, components in teal, repeats in magenta, subcomponents in green, escape sequences italicized. You see structure at a glance.
Rule library, auto-selected
Save ORM^O01, ORU^R01, ADT^A01, SIU^S12, DFT^P03 — the validator reads MSH-9 and MSH-12 and picks the right rule. Don't have one? Click Extract and it builds a candidate from the message.
Grid AND console views
Sortable grid with colour-coded rows. PS1-style monospace console output you can paste into a ticket, a Slack message, or a runbook. Use whichever matches your brain that morning.
Soft-delete with restore
You'll delete a saved rule by accident eventually. Or share a machine with a colleague who tidies. Recover any time from File → Restore Deleted Rules.
PHI never leaves your laptop
Web-based validators are a non-starter for healthcare. The only network call this app makes is the OIDC sign-in to confirm your free-tier account. Message content stays on localhost.
Honest about scope: we validate structure — presence, order, optionality, repeatability. We don't validate field-level content, data types, or table values. That's a different tool. Pair us with your engine's field-level checks and you have a complete pipeline.
Up and running in three steps
Install the app
Single-binary download for Windows (macOS and Linux coming soon). First launch prompts you to sign in or register with a free Neureau account.
Pick a rule, paste a message
Pick from your saved rule library or paste a custom abstract-syntax rule. Browse to a .hl7 file or paste raw HL7 text — the editor highlights it as you go.
Run, iterate, ship
One click. Results appear in both grid and console views with a summary at the bottom. Saved rules persist for next session. Total time from launch to first result: under thirty seconds.
Built for the people who keep healthcare data moving
- HL7 integration engineers at hospitals, payers, labs, and EHR vendors
- Integration analysts doing 11pm production triage
- Interface developers building Mirth / Cloverleaf / Iguana / Corepoint channels
- HIE engineers validating partner-supplied feeds
- EHR implementation teams verifying vendor-supplied test messages
- Healthcare AI / NLP teams validating training-data HL7 feeds
If you've ever opened a 60-segment ORU in vim and started counting pipes, this tool is for you.
Pricing
Free for everyone who registers a Neureau account. The standalone desktop validator described on this page will remain free.
We use sign-in to keep you informed about other Neureau capabilities you might benefit from (NeureauAI Engine, our healthcare data products) and to send the occasional product update. You can unsubscribe any time without losing app access.
We may introduce paid tiers in the future for enterprise features (team rule libraries, SSO federation, hosted API access, deeper Mirth / Iguana integrations).
What's coming
We ship small and often. Already shipped and on the public roadmap:
- Live HL7 syntax colouring in the paste editor
- Soft-delete + restore for saved rules
- Auto-rule-selection from MSH-9 / MSH-12
- Console-style results view alongside the grid
- Extract-rule-from-message
- Precise error recovery (no more cascades from one bad segment)
- Rule-aware segment colouring (required = green, optional = blue, repeating = purple, unknown = red)
- macOS + Linux native builds
- Bulk file mode — validate a folder of messages and export to CSV
- Mirth Connect deep-link integration
- Team rule libraries (shared via cloud account)
- REST API for CI/CD integration
Have a feature request? Tell us at contact.
Welcome.
If you build interfaces, write transformations, or troubleshoot HL7 in any form — we built this for you.