LastQty (FIX tag 32)

QtyFIX 4.4FIX 4.2

LastQty (tag 32) is a Qty field defined in FIX 4.4 and FIX 4.2. It appears in 5 message types and is required in 1 of them. FIX 4.2 calls this field LastShares; the tag number is unchanged, so the two are the same field on the wire.

Also known as LastShares

FIX 4.2 calls tag 32 LastShares. It is the same field on the wire — only the name changed — so a message encoded by either side interoperates.

At a glance

Tag: 32
Name: LastQty
Datatype: Qty (float)
Dialects: FIX 4.4 and FIX 4.2
Messages: 5

What the specification says

FIX 4.4

Quantity (e.g. shares) bought/sold on this (last) fill. (Prior to FIX 4.2 this field was of type int)

FIX 4.2

Quantity of shares bought/sold on this (last) fill. Field not required for ExecTransType = 3 (Status) (Prior to FIX 4.2 this field was of type int)

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

A real message using tag 32

ExecutionReport · FIX 4.4

Tag	Field	Wire value	Meaning
8	BeginString	FIX.4.4
9	BodyLength	144
35	MsgType	8	Execution Report
49	SenderCompID	BOARTEAM
56	TargetCompID	COUNTERPARTY
34	MsgSeqNum	2
52	SendingTime	20240101-12:00:00.000
37	OrderID	ORD-10042
17	ExecID	EXEC-88117
150	ExecType	0	New
39	OrdStatus	0	New
54	Side	1	Buy
32	LastQty	1000000
151	LeavesQty	0
14	CumQty	1000000
6	AvgPx	1.09215
10	CheckSum	015

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 32 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	FIX 4.4	FIX 4.2	Where in the message
AllocationInstruction	J	Conditional	Optional	inside the ExecAllocGrp component
AllocationReport	AS	Conditional	—	inside the ExecAllocGrp component
DontKnowTrade	Q	Optional	Optional	directly on the message body
ExecutionReport	8	Conditional	Optional	directly on the message body
TradeCaptureReport	AE	Required	—	directly on the message body

Wire format

A decimal quantity. Fractional quantities are legal, which is why this is a float family rather than an integer. @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 32 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[32];field?.name;   // "LastQty"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