AvgParPx (FIX tag 860)

PriceFIX 4.4

AvgParPx (tag 860) is a Price field defined in FIX 4.4. It appears in 3 message types, always optionally.

At a glance

Tag: 860
Name: AvgParPx
Datatype: Price (float)
Dialects: FIX 4.4
Messages: 3

What the specification says

Used to express average price as percent of par (used where AvgPx field is expressed in some other way)

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

A real message using tag 860

AllocationInstruction · FIX 4.4

Tag	Field	Wire value	Meaning
8	BeginString	FIX.4.4
9	BodyLength	141
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
54	Side	1	Buy
53	Quantity	1000000
6	AvgPx	1.09215
860	AvgParPx	1.09210
75	TradeDate	20240101
10	CheckSum	169

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 860 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	directly on the message body
AllocationReport	AS	Optional	directly on the message body
Confirmation	AK	Optional	directly on the message body

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 860 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[860];field?.name;   // "AvgParPx"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