Modify Order

Hyperliquid

Endpoint

POST /exchange

Description

Supports both single modify ("modify") and batch modify ("batchModify"). Use the exchange signing flow with the account owner or an approved API wallet. Hyperliquid and Polymarket outcome orders cannot be modified; cancel and replace them instead. Spot modifications are available only when enabled by the deployment and only for eligible resting limit orders.

Request Body

Parameter	Type	Description
`action`*	object	Modify payload
`nonce`*	number	Replay-protection nonce, e.g., `1701234567890`
`signature`*	object	EIP-712 signature
`expiresAfter`	number	Optional signed expiration time in Unix milliseconds

action

Field	Type	Description
`type`*	string	`"modify"` or `"batchModify"`
`oid`	string \| number	Order ID for a single modify, e.g., `"0x1a2b3c..."`
`order`	object	Replacement fields for one order
`modifies`	array	Batch of modify items

For modify, both oid and order are required. For batchModify, modifies must contain at least one item. Use the string Notional order ID returned by the API, not a numeric venue order ID.

action.modifies[]

Field	Type	Description
`oid`*	string \| number	Notional order ID, e.g., `"0x1a2b3c..."`
`order`*	object	Replacement order fields

action.order and action.modifies[].order

Field	Type	Description
`p`*	string	New signed price, e.g., `"50500.0"`
`s`*	string	New total order size, e.g., `"0.2"`
`r`	boolean	Optional reduce-only value; must match the existing order
`t`*	object	Order type config; must match immutable trigger/TIF properties

The market and side remain those of the stored order. s is the new total size, including any already filled quantity. A limit order’s t.limit.tif must remain unchanged (Gtc, Ioc, or Alo). A trigger’s tpsl and isMarket fields are also immutable. Local stop-market TP/SL can be modified before it fires; venue-backed trigger orders require cancel and replacement. A resting reduce-only order may be modified. Its new size is admitted against the market’s free close capacity: a size that would push your live closing orders past the position is rejected with code: "CLOSE_CAPACITY_EXCEEDED" and free: "<size>" (the remaining close capacity as a decimal string), and a modify of a closing order while an immediate close is superseding the market’s resting closes is rejected with code: "CLOSE_IN_PROGRESS". financing is unsupported and explicitly rejected in the replacement order specification.

Response

The server echoes the incoming action type:

200: Confirmed
200: Pending
200: Rejected

{
  "status": "ok",
  "response": {
    "type": "modify",
    "data": {
      "statuses": [
        {
          "resting": {
            "oid": "0x1a2b3c..."
          }
        }
      ]
    }
  },
  "metadata": {
    "results": [
      {
        "oid": "0x1a2b3c...",
        "status": "confirmed",
        "orderId": "0x1a2b3c...",
        "venueOid": 12345
      }
    ]
  }
}

{
  "status": "ok",
  "response": {
    "type": "modify",
    "data": {
      "statuses": [
        {
          "pending": {
            "cloid": "0x1a2b3c..."
          }
        }
      ]
    }
  },
  "metadata": {
    "results": [
      {
        "oid": "0x1a2b3c...",
        "status": "pending",
        "orderId": "0x1a2b3c..."
      }
    ]
  }
}

{
  "status": "ok",
  "response": {
    "type": "modify",
    "data": {
      "statuses": [
        {
          "error": "Order was never placed, already canceled, or filled"
        }
      ]
    }
  },
  "metadata": {
    "results": [
      {
        "oid": "0x1a2b3c...",
        "status": "rejected",
        "orderId": "0x1a2b3c...",
        "error": "Order was never placed, already canceled, or filled"
      }
    ]
  }
}

Status Variants

Variant	Fields	Meaning
`resting`	`oid`	Exchange confirmed the modify
`pending`	`cloid`	Final venue confirmation is not yet available
`error`	Message	Validation or venue failure

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Info

Analytics

Exchange

WebSocket

Endpoint

Description

Request Body

action

action.modifies[]

action.order and action.modifies[].order

Response

Status Variants

​Endpoint

​Description

​Request Body

​action

​action.modifies[]

​action.order and action.modifies[].order

​Response

​Status Variants

Endpoint

Description

Request Body

action

action.modifies[]

action.order and action.modifies[].order

Response

Status Variants