OrderAvgPx (FIX tag 799)

PriceFIX 4.4

OrderAvgPx (tag 799) is a Price field defined in FIX 4.4. It appears in 4 message types, always optionally.

At a glance

Tag: 799
Name: OrderAvgPx
Datatype: Price (float)
Dialects: FIX 4.4
Messages: 4

What the specification says

Average price for a specific order

Descriptions are quoted from the FIX Orchestra sources under the Apache 2.0 licence.

A real message using tag 799

AllocationInstruction · FIX 4.4

Tag	Field	Wire value	Meaning
8	BeginString	FIX.4.4
9	BodyLength	184
35	MsgType	J	Allocation Instruction
49	SenderCompID	BOARTEAM
56	TargetCompID	COUNTERPARTY
34	MsgSeqNum	2
52	SendingTime	20240101-12:00:00.000
70	AllocID	EXAMPLE
71	AllocTransType	0	New
626	AllocType	1	Calculated (includes MiscFees and NetMoney)
857	AllocNoOrdersType	0	Not specified
73	NoOrders2 entries	2	repeating group
11	ClOrdID	ORD-10042
799	OrderAvgPx	1.09210
11	ClOrdID	ORD-10042
799	OrderAvgPx	1.09210
54	Side	1	Buy
53	Quantity	1000000
6	AvgPx	1.09215
75	TradeDate	20240101
10	CheckSum	041

Edit and decode it yourself

Shown with | separators for readability. On the wire FIX uses SOH (0x01), an invisible control byte — and because BodyLength and CheckSum are computed over the actual bytes, the two forms have different checksums. Both are valid and both decode here.

Open in the full decoder →

Generated from the FIX 4.4 dictionary and verified at build time: it parses and validates with no issues. Open the decoder to try your own message.

Where tag 799 appears

Requiredness is a property of the message, not of the field: the same tag can be optional in one message and conditionally required in another.

Message	MsgType	Requiredness	Where in the message
AllocationInstruction	J	Optional	inside the OrdAllocGrp component
AllocationReport	AS	Optional	inside the OrdAllocGrp component
Confirmation	AK	Optional	inside the OrdAllocGrp component
ConfirmationRequest	BH	Optional	inside the OrdAllocGrp component

Wire format

A decimal price. Precision is a venue convention, not a protocol rule, so compare the raw string when exactness matters. @boarteam/fix parses the value as a number and reports parse/invalid-float when it does not lex as one; the raw string is kept so precision and trailing zeros are never lost.

Read tag 799 in TypeScript

decode.tsts

import { createFixEngine } from "@boarteam/fix";import { dictionary } from "@boarteam/fix-dict-fix44";const fix = createFixEngine(dictionary);const { message, issues } = fix.parse(raw);const field = message.fields[799];field?.name;   // "OrderAvgPx"field?.raw;    // the verbatim wire stringfield?.value;  // coerced to a number

Decode this in your own code

The same engine that produced the decoded example above is an Apache-2.0 npm package with zero runtime dependencies. It runs in Node and in the browser, and parse() returns problems as data instead of throwing.

npm i @boarteam/fix @boarteam/fix-dict-fix44

Try the decoder Source on GitHub