Prime FIX Messages

The baseline specification for this API is FIX 4.2. Below, we've noted the places in which the FIX API for Coinbase Prime extends (or clarifies) the FIX spec. For example, there are custom tags with a four-digit number range, as allowed by the standard, which are unique to Prime.

A standard header must be present at the start of every message in both directions. You should configure your sessions so that

• SenderCompID = the Service Account ID associated with the API key as your SenderCompID
• TargetCompID = the string COIN

This is typically accomplished via your FIX client's configuration file.

info

A Service Account ID is a unique ID generated when you create an API Key. You can find it to the right of your API Key in Settings.

Tag	Name	Description
8	BeginString	Must be FIX.4.2
49	SenderCompID	The Service Account ID (on messages from the client)
56	TargetCompID	Must be COIN (on messages from the client)

Logon (A)

Sent by the client to initiate a session and by the server as an acknowledgement. Only one session can exist per connection -- sending a Logon message within an established session results in an error.

The Logon message sent by the client must be signed for security. The prehash string has the following fields, each joined by the empty string:

{timestamp}A{seqNum}{apiKey}{targetComp}{passphrase}.

There is no trailing separator. The RawData field should be a base64 encoding of the HMAC signature.

To establish multiple FIX connections, you must generate a new API key for each one. All messages must have a SendingTime value within 5 seconds of server time in UTC or they are rejected.

caution

Only one session can exist per connection (or API key) at a time.

Tag	Name	Description
1	Account	Portfolio ID associated with the API key
96	RawData	Client message signature (see below)
554	Password	Client API passphrase
9407	Access Key	Client API key

Python Example

def toAdmin(self, message, sessionID):
    if message.getHeader().getField(35) == "A":
        rawData = self.sign(message.getHeader().getField(52), message.getHeader().getField(35),
                            message.getHeader().getField(34), self.API_KEY, message.getHeader().getField(56),
                            self.PASSPHRASE)
        message.setField(fix.StringField(554, self.PASSPHRASE))
        message.setField(fix.StringField(96, rawData))
        message.setField(fix.StringField(9407, self.API_KEY))
        msg = message.toString().replace(__SOH__, "|")
        logfix.info("(Admin) S >> %s" % msg)
        return
    else:
        return

def sign(self, t, msg_type, seq_num, access_key, target_comp_id, passphrase):
    message = ''.join([t, msg_type, seq_num, access_key, target_comp_id, passphrase]).encode("utf-8")
    hmac_key = self.API_SECRET
    signature = hmac.new(hmac_key.encode('utf-8'), message, hashlib.sha256)
    sign_b64 = base64.b64encode(signature.digest()).decode()
    return sign_b64

JavaScript Example

// create a new Logon message
var logon = new Msgs.Logon();
logon.SendingTime = new Date();
logon.passphrase = '...';
var presign = [
   logon.SendingTime,
   logon.MsgType,
   session.outgoing_seq_num,
   apiKey,
   session.target_comp_id,
   passphrase
].join('');
// add the presign string to the RawData field of the Logon message
logon.RawData = sign(presign, secret);
// send the logon message to the server
session.send(logon);

function sign(what, secret) {
   var key = Buffer.from(secret, 'base64');
   var hmac = crypto.createHmac('sha256', key);
   return hmac.update(what).digest('base64');
}

New Order Single (D)

Sent by the client to enter an order. Not every tag is required for every order -- it depends on the target strategy used. See the table below for more information.

Tag	Name	Description	Notes
1	Account	The portfolio ID
11	ClOrdID	A string selected by client to identify the order
38	OrderQty	Order size in base units (e.g., BTC). Either this or CashOrderQty must be supplied.
40	OrderType	The order type; see the table below for a list.	Must match TargetStrategy
44	Px	Indicates the price of the order	Required for Limit and TWAP orders
54	Side	Must be 1 to buy or 2 to sell
55	Symbol	The product to be traded (e.g., BTC-USD)
59	TimeInForce	A valid TimeInForce value; see the table below for a list.	Must match TargetStrategy
99	StopPx	Stop price for Stop Limit order	Specifies the stop price at which the order activates. The order is activated if the last trade price on Coinbase Exchange crosses the stop price specified on the order.
126	ExpireTime	Represents the time and date of order expiration	Required for TWAP/VWAP orders and Limit GTD orders, unless ParticipationRate is specified (TWAP/VWAP only)
152	CashOrderQty	Order size in quote units (e.g., USD)	Either this or OrderQty must be supplied.
168	EffectiveTime	Represents the start time	Required for TWAP/VWAP orders
210	MaxShow	Maximum quantity within an order to be shown to other customers (Display Size)	Only available for LIMIT orders
847	TargetStrategy	The target strategy of the order to place; see the table below for a list.	Requires ExpireTime and EffectiveTime for TWAP/VWAP orders. Must be SL and requires StopPx for Stop Limit orders.
849	ParticipationRate	Represents the estimated percent of volume for TWAP/VWAP order types.	Can be used instead of ExpireTime which it computes based on historical participation of volume rate.
8999	IsRaiseExact	Y or N, is this a raise exact order. If Y, the asset amount sold is adjusted so the total received after fees equals the input size.	Optional, defaults to N. Supported for SELL, Size In Quote orders only.

TargetStrategy Values

caution

Requires ExpireTime and EffectiveTime for TWAP/VWAP orders. Must be "SL" and requires StopPx for Stop Limit orders.

Value	Description	OrderType	TimeInForce
L	Limit order	Must be 2 (Limit)	Must be 1 (GTC) or 3 (IOC) or 4 (FOK) or 6 (GTD) Limit FOK currently only accepts size in base orders and orders are only routed to the Coinbase Exchange 44 (price) must also be provided
M	Market order	Must be 1 (Market)	Must be 3 (IOC)
T	TWAP order	Must be 2 (Limit)	Must be 6 (GTD); 44 (price) must also be provided
V	VWAP order	Must be 2 (Limit)	Must be 6 (GTD); 44 (price) must also be provided
SL	Stop Limit order	Must be 2 (Limit)	Must be 1 (GTC) or 6 (GTD); 44 (price) and 99 (StopPx) must also be provided

OrderType Values

Value	Description
1	Market
2	Limit

TimeInForce Values

caution

Must match TargetStrategy

Value	Description
1	Good Till Cancel (GTC)
3	Immediate or Cancel (IOC)
4	FILL_OR_KILL (FOK)
6	Good Till Date (GTD)

Order Cancel Request (F)

Sent by the client to cancel an order.

Tag	Name	Description	Notes
1	Account	The portfolio ID
11	ClOrdId	ClOrdId identifying this cancel request
37	OrderID	OrderID assigned by Coinbase (available in any of the Execution Report messages)
38	OrderQty	Accepted order quantity	You must supply this tag or CashOrderQty (depending on whichever you originally submitted)
41	OrigClOrdID	ClOrdID from the New Order Single	You must also supply an OrderID
54	Side	Must be 1 to buy or 2 to sell (depending on whichever you originally submitted)
55	Symbol	The product from the original order (e.g., BTC-USD)
152	CashOrderQty	Order size in quote units (e.g., USD)	You must supply this tag or OrderQty (depending on which you submitted)

Order Status Request (H)

Sent by the client to obtain information about pending and completed orders.

Tag	Name	Description	Notes
11	ClOrdID	ClOrdID of the order to be sent back
37	OrderID	OrderID of the order to be sent back	Required
54	Side	Must be 1 to buy or 2 to sell
55	Symbol	The product to be traded (e.g., BTC-USD)

Python Example

def get_order_status(self, order_id, clord_id):
   '''Send Order Status Request Message (H)'''
   order_status_message = fix.Message()
   header = order_status_message.getHeader()
   header.setField(fix.MsgType(fix.MsgType_OrderStatusRequest))  # 35 = H
   order_status_message.setField(fix.OrderID(order_id))
   order_status_message.setField(fix.ClOrdID(clord_id))
   order_status_message.setField(fix.Side(fix.Side_BUY))
   order_status_message.setField(fix.Symbol("DOGE-USD"))
   fix.Session.sendToTarget(order_status_message, self.sessionID)

FIX Message Request: (35=H)

8=FIX.4.2|9=181|35=H|34=12|49=SENDERCOMPID|52=20220526-16:12:08.000|56=COIN|11=CLOrdID|37=OrderID|54=1|55=DOGE-USD|10=011|

FIX Message Response:

8=FIX.4.2|9=307|35=8|34=13|49=COIN|52=20220526-16:12:08.134|56=TARGETCOMPID|1=ACCOUNT|6=0|11=CLOrdID|14=0|17=ExecID|20=1|32=0.0|37=OrderID|38=100|39=4|54=1|55=DOGE-USD|150=4|151=100|10=255|

Execution Report (8)

Sent by the server when an order is accepted, rejected, filled, or canceled. Also sent when the user sends an OrderStatusRequest.

Tag	Name	Description	Notes
6	AvgPx	The average price of the order
11	ClOrdID	ClOrdID of order to be sent back
12	Commission	The Commission incurred for this fill
14	CumQty	Total amount filled on this order
17	ExecID	Unique ID for fill
31	LastPx	Price of the fill if ExecType indicates a fill
32	LastShares	Amount filled (if ExecType=1). Also called LastQty as of FIX 4.3
37	OrderID	OrderID from the ExecutionReport
38	OrderQty	OrderQty as accepted	You must supply this tag or CashOrderQty (depending on whichever you originally submitted)
39	OrdStatus	Order status as of the current message
50	SenderSubID	ID of the user that initiated the request (e.g. submitted the NOS)
54	Side	Must be 1 to buy or 2 to sell
55	Symbol	Symbol of the original order
103	OrdRejReason	See OrdRejReason Values table
150	ExecType	Must be 1 (Partial fill) for fills, 4 for cancelled, etc
151	LeavesQty	Amount of order remaining
152	CashOrderQty	Order size in quote units (e.g., USD)	You must supply this tag or OrderQty (depending on whichever you originally submitted)
30	LastMkt	Market of execution for last fill

OrdRejReason Values

OrdRejReason	Description
0	Broker option
1	Unknown symbol
2	Exchange closed
3	Order exceeds limit
4	Too late to enter
5	Unknown Order
6	Duplicate Order

ExecType Values

ExecType	Description
0	New Order
1	Partial Fill
2	Filled
3	Done
4	Canceled
6	Pending Cancel
7	Stopped
8	Rejected
D	Restated
A	Pending New
I	Order Status

Order Cancel Reject (9)

Sent by the server when an Order Cancel Request cannot be satisfied, e.g., because the order is already canceled or completely filled.

Tag	Name	Description
11	ClOrdID	The same value provided by the original cancel request
37	OrderID	The same value provided by the original cancel request
39	OrdStatus	The order status; see the table below for a list.
41	OrigClOrdID	The same value provided by the original cancel request
102	CxlRejReason	The reason the order was rejected
434	CxlRejResponseTo	The rejection response; see the table below for a list

OrdStatus Values

Valid Values	Description
0	New
1	Partially filled
2	Filled
3	Done for day
4	Canceled
5	Replaced
6	Pending Cancel (e.g., result of Order Cancel Request <F>)
7	Stopped
8	Rejected
9	Suspended
A	Pending New
B	Calculated
C	Expired
D	Accepted for bidding
E	Pending Replace (e.g., result of Order Cancel/Replace Request <G>)

CxlRejResponseTo Values

Valid Values	Description
1	Order Cancel Request <F>
2	Order Cancel/Replace Request <G>

Reject (3)

Sent by either side upon receipt of a message which cannot be processed, e.g., due to missing fields or an unsupported message type.

Tag	Name	Description
45	RefSeqNum	MsgSeqNum of the rejected incoming message
58	Text	Human-readable description of the error (optional)
371	RefTagID	Tag number of the field which caused the reject (optional)
372	RefMsgType	MsgType of the rejected incoming message
373	SessionRejectReason	Code to identify reason for the reject (for session-level rejections only)