ContractMultiplier (FIX tag 231)

floatFIX 4.4FIX 4.2

ContractMultiplier (tag 231) is a float field defined in FIX 4.4 and FIX 4.2. It appears in 59 message types, always optionally.

At a glance

Tag: 231
Name: ContractMultiplier
Datatype: float
Dialects: FIX 4.4 and FIX 4.2
Messages: 59

What the specification says

FIX 4.4

Specifies the ratio or multiply factor to convert from "nominal" units (e.g. contracts) to total units (e.g. shares) (e.g. 1.0, 100, 1000, etc). Applicable For Fixed Income, Convertible Bonds, Derivatives, etc. In general quantities for all classes should be expressed in the basic unit of the instrument, e.g. shares for equities, nominal or par amount for bonds, currency for foreign exchange. When quantity is expressed in contracts, e.g. financing transactions and bond trade reporting, ContractMultiplier should contain the number of units in one contract and can be omitted if the multiplier is the default amount for the instrument, i.e. 1,000 par of bonds, 1,000,000 par for financing transactions.

FIX 4.2

Specifies the ratio or multiply factor to convert from contracts to shares (e.g. 1.0, 100, 1000, etc). Applicable For Fixed Income, Convertible Bonds, Derivatives, etc. Note: If used, quantities should be expressed in the "nominal" (e.g. contracts vs. shares) amount.

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

A real message using tag 231

NewOrderSingle · FIX 4.4

Tag	Field	Wire value	Meaning
8	BeginString	FIX.4.4
9	BodyLength	119
35	MsgType	D	Order – Single
49	SenderCompID	BOARTEAM
56	TargetCompID	COUNTERPARTY
34	MsgSeqNum	2
52	SendingTime	20240101-12:00:00.000
11	ClOrdID	ORD-10042
231	ContractMultiplier	1.0
54	Side	1	Buy
60	TransactTime	20240101-12:00:00.000
40	OrdType	1	Market
10	CheckSum	091

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 231 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
Advertisement	7	Optional	Optional	inside the Instrument component
AllocationInstruction	J	Optional	Optional	inside the Instrument component
AllocationReport	AS	Optional	—	inside the Instrument component
AssignmentReport	AW	Optional	—	inside the Instrument component
CollateralAssignment	AY	Optional	—	inside the Instrument component
CollateralInquiry	BB	Optional	—	inside the Instrument component
CollateralInquiryAck	BG	Optional	—	inside the Instrument component
CollateralReport	BA	Optional	—	inside the Instrument component
CollateralRequest	AX	Optional	—	inside the Instrument component
CollateralResponse	AZ	Optional	—	inside the Instrument component
Confirmation	AK	Optional	—	inside the Instrument component
CrossOrderCancelReplaceRequest	t	Optional	—	inside the Instrument component
CrossOrderCancelRequest	u	Optional	—	inside the Instrument component
DerivativeSecurityList	AA	Optional	—	inside RelSymDerivSecGrp › Instrument
DontKnowTrade	Q	Optional	Optional	inside the Instrument component
Email	C	Optional	Optional	inside InstrmtGrp › Instrument
ExecutionReport	8	Optional	Optional	inside the Instrument component
IOI	6	Optional	Optional	inside the Instrument component
ListStrikePrice	m	Optional	Optional	inside InstrmtStrkPxGrp › Instrument
MarketDataIncrementalRefresh	X	Optional	Optional	inside MDIncGrp › Instrument
MarketDataRequest	V	Optional	Optional	inside InstrmtMDReqGrp › Instrument
MarketDataSnapshotFullRefresh	W	Optional	Optional	inside the Instrument component
MassQuote	i	Optional	Optional	inside QuotSetGrp › QuotEntryGrp › Instrument
MassQuoteAcknowledgement	b	Optional	Optional	inside QuotSetAckGrp › QuotEntryAckGrp › Instrument
MultilegOrderCancelReplace	AC	Optional	—	inside the Instrument component
NewOrderCross	s	Optional	—	inside the Instrument component
NewOrderList	E	Optional	Optional	inside ListOrdGrp › Instrument
NewOrderMultileg	AB	Optional	—	inside the Instrument component
NewOrderSingle	D	Optional	Optional	inside the Instrument component
News	B	Optional	Optional	inside InstrmtGrp › Instrument
OrderCancelReplaceRequest	G	Optional	Optional	inside the Instrument component
OrderCancelRequest	F	Optional	Optional	inside the Instrument component
OrderMassCancelReport	r	Optional	—	inside the Instrument component
OrderMassCancelRequest	q	Optional	—	inside the Instrument component
OrderMassStatusRequest	AF	Optional	—	inside the Instrument component
OrderStatusRequest	H	Optional	Optional	inside the Instrument component
PositionMaintenanceReport	AM	Optional	—	inside the Instrument component
PositionMaintenanceRequest	AL	Optional	—	inside the Instrument component
PositionReport	AP	Optional	—	inside the Instrument component
Quote	S	Optional	Optional	inside the Instrument component
QuoteCancel	Z	Optional	Optional	inside QuotCxlEntriesGrp › Instrument
QuoteRequest	R	Optional	Optional	inside QuotReqGrp › Instrument
QuoteRequestReject	AG	Optional	—	inside QuotReqRjctGrp › Instrument
QuoteResponse	AJ	Optional	—	inside the Instrument component
QuoteStatusReport	AI	Optional	—	inside the Instrument component
QuoteStatusRequest	a	Optional	Optional	inside the Instrument component
RFQRequest	AH	Optional	—	inside RFQReqGrp › Instrument
RequestForPositions	AN	Optional	—	inside the Instrument component
RequestForPositionsAck	AO	Optional	—	inside the Instrument component
SecurityDefinition	d	Optional	Optional	inside the Instrument component
SecurityDefinitionRequest	c	Optional	Optional	inside the Instrument component
SecurityList	y	Optional	—	inside SecListGrp › Instrument
SecurityListRequest	x	Optional	—	inside the Instrument component
SecurityStatus	f	Optional	Optional	inside the Instrument component
SecurityStatusRequest	e	Optional	Optional	inside the Instrument component
TradeCaptureReport	AE	Optional	—	inside the Instrument component
TradeCaptureReportAck	AR	Optional	—	inside the Instrument component
TradeCaptureReportRequest	AD	Optional	—	inside the Instrument component
TradeCaptureReportRequestAck	AQ	Optional	—	inside the Instrument component

Wire format

A decimal number. The wire form keeps its trailing zeros, which is why decoders expose the raw string alongside the parsed number. @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 231 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[231];field?.name;   // "ContractMultiplier"field?.raw;    // the verbatim wire stringfield?.value;  // coerced to a number

Other float fields

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