HL7 Parser | HL7 v2 Message Viewer Online

HL7 parser and viewer for v2 messages. Splits ADT, ORU and ORM messages into named segments, fields and components, flags MSH errors, and keeps PHI local. Designed specifically for developers and professionals, this free online analyzer runs entirely in your browser to process tasks quickly and securely. Enjoy unlimited usage with no data tracking and no registration required.

Also known as: hl7 parser · hl7 parser online · hl7 viewer online · hl7 message parser · hl7 v2 message viewer · parse hl7 message online free · hl7 segment decoder · hl7 to json · hl7 adt message parser · oru r01 parser

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HL7 Message Input

Parsed Message

Every segment, field and component will appear here with its HL7 v2.5.1 name.

About HL7 Parser

An HL7 parser is used to read the HL7 v2 messages that hospital, lab and EHR systems exchange, such as ADT admissions and ORU lab results. This tool splits a message into segments, fields, repetitions and components, names each position from the HL7 v2.5.1 tables, decodes escape sequences, and flags the header and sequencing mistakes that make interfaces reject messages.

Key Features

Names every field and component for MSH, PID, PV1, ORC, OBR, OBX, NK1, IN1 and 15 more segments
Reads the delimiters from MSH-1 and MSH-2, so custom encoding characters still parse
Decodes \F\, \S\, \T\, \R\, \E\, \.br\ and \Xhh\ escape sequences
Explains coded values such as OBX-8 abnormal flags, PV1-2 patient class and MSA-1 acknowledgment codes
Flags an empty MSH-9 or MSH-10, missing PID-3, non-numeric NM results and out-of-order set IDs
Strips MLLP framing bytes and exports the parsed message as JSON or a text report

Use Cases

Debug an ADT^A01 feed that a Mirth or Rhapsody interface engine keeps rejecting
Check which LOINC codes and units a reference lab sends in OBX segments before go-live
Read an ORU^R01 result a clinician says arrived with the wrong patient
Compare a vendor's HL7 spec against the messages their system actually sends
Review messages during HIPAA-scoped interface testing without uploading PHI anywhere
Teach new integration analysts how MSH, PID and PV1 fit together

Supported Formats

HL7 v2.x pipe-delimited

.hl7

.txt

MLLP-framed messages

CR, LF or CRLF segment endings

Related Keywords

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oru r01 parser

What is the structure of an HL7 v2 message?

An HL7 v2 message is a list of segments separated by carriage returns. Each segment starts with a three-letter ID such as MSH or PID, and its fields are separated by the character right after MSH, almost always a pipe. Inside a field, a caret separates components, a tilde separates repetitions and an ampersand separates subcomponents, and MSH-2 declares those characters. The MSH segment counts its own field separator as MSH-1, which is why MSH field numbers look shifted by one compared with every other segment.

Does this tool upload my HL7 messages?

No. Parsing happens in your browser and nothing is sent to a server, which matters because HL7 messages usually carry protected health information. Clear the page when you finish on a shared machine.

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Frequently asked questions

What is HL7 Parser used for?

HL7 parser and viewer for v2 messages. Splits ADT, ORU and ORM messages into named segments, fields and components, flags MSH errors, and keeps PHI local.

Is HL7 Parser free to use?

Yes. HL7 Parser is completely free with no usage limits, and there is no paid tier required to use it.

Do I need an account to use HL7 Parser?

No. HL7 Parser works immediately in your browser with no signup, login, or email address required.

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