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The cancel action removes resting orders from the order book using the exchange-assigned order IDs returned in the resting.oid field when you originally placed them. An entry without o can instead locate the order by its client order ID c. You can cancel up to 10 orders in a single signed request, mixing contracts freely within the batch.

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Endpoint

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Request

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Action Fields

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string
required
type (required) — Fixed value: "cancel".
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array
required
cancels (required) — Array of cancel objects. Maximum 10 per request; more returns BATCH_TOO_LARGE. Each entry identifies the contract and the order to cancel.
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boolean
sync — Envelope-level, beside action, and not signed. true returns HTTP 200 with one result per cancel; false returns HTTP 202 and the results arrive on orderUpdates. When omitted, the server default applies. Must be a JSON boolean. See Synchronous and asynchronous responses.

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Cancel Object Fields

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int32
required
a (asset) (required) — The integer contract ID for the order you want to cancel. Must match the contract the order was placed on.
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int64
o (orderId) — The exchange-assigned order ID from the resting.oid field returned when the order was placed. When o is present it identifies the order and c is ignored.
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string
c (clientOrderId) — The client order ID set at placement, used to locate the order only when o is omitted. Only decimal digits (0–9) are accepted, at most 20 bytes, within the int64 range; otherwise the request returns 400 INVALID_PARAM with errors[].reason INVALID_FORMAT (OUT_OF_RANGE outside int64). The format check applies only when c is used to locate the order.

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Response

Two status codes are possible. With sync: true the server answers HTTP 200 with the result shown below; with sync: false it answers HTTP 202, acknowledging the request for asynchronous processing:
count is always 1. On a 202 the per-item outcome arrives on the orderUpdates channel instead. Without sync the server default decides — handle both.
The response contains one status entry per cancel object in the same index order as your request.
Both cancellations succeeded. Each successful entry is the plain string "success", in the same order as cancels[].

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Response Fields

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array
One entry per cancel object in request order. Each entry is either:
  • The string "success" — the order was found and removed from the book.
  • An object {"error": "<reason>"} — the cancellation failed; the reason string explains why.
A top-level "status": "ok" does not mean every individual cancellation succeeded. Always inspect each element of statuses to detect per-order failures.

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Errors