Errors

The Quidax API uses standard HTTP status codes to indicate whether a request succeeded or failed.

Error Code	Status	Meaning	Common Causes	Fix
400	Bad request	Your request is missing a required field or contains an invalid value. We couldn't process it as sent.	Missing currency, amount, or fund_uid on a withdrawal Unsupported currency ticker (e.g. usdc misspelled or not in the allowed list) Sending a market order without specifying the market pair Providing amount as a number instead of a string	Check all required body and path params against the endpoint's spec Verify the currency ticker is in the supported currencies list Ensure amount is passed as a string (e.g. "0.0001")
401	Unauthorized	We could not authenticate the request. Your API key is missing, invalid, or has been revoked.	Authorization header not set or malformed (must be Bearer ) Using a test key against the production base URL or vice versa API key has been regenerated on the dashboard but old key is still in use	Set the header exactly as Authorization: Bearer s3cr3tk3y Regenerate your key from the Quidax developer dashboard if it may have been compromised Never expose your key client-side — always call from your server
403	Forbidden	Your key is valid, but the authenticated account doesn't have permission to perform this specific action.	Attempting to withdraw from or manage a sub-account that doesn't belong to your master account Trying to cancel an order or withdrawal that belongs to a different user Using a sub-account key to perform master-account-only actions	Use me as user_id for master account actions; use the actual sub-account ID for sub-account actions Confirm the sub-account was created under the authenticated master account
404	Not Found	The resource you requested doesn't exist — either the ID is wrong or the record was never created.	Fetching a withdrawal, order, or swap using an ID that doesn't exist or belongs to another account Requesting a wallet for a currency that hasn't been initialised yet for that sub-account Looking up a payment address before one has been generated (addresses are created on demand)	For payment addresses, call the Fetch Payment Address endpoint first to trigger address generation Double-check the ID in your path params — use the id field returned in prior API responses Ensure the resource belongs to the authenticated account making the request
429	Too Many Requests	You've exceeded the rate limit for the endpoint.	Exceeding 300 requests/min across general endpoints Exceeding 20 requests/sec on the wallet address generation endpoint (POST /wallets/{currency}/addresses) Polling deposit or order status in a tight loop instead of using webhooks	Implement exponential backoff with retry on 429 responses Queue and batch requests rather than sending in parallel bursts Use webhooks (e.g. deposit.successful, withdraw.successful) instead of polling
5XX	Server Error	An unexpected error occurred on our side. The request may have been received but the outcome is uncertain.	Temporary infrastructure issues on our end Calling over plain HTTP instead of HTTPS (causes a 301 redirect that can surface as a 5XX) A swap quotation being confirmed after the 15-second validity window has expired	Always use https:// — non-TLS requests return 301 and can leak your API key For swaps: confirm within 15 seconds or call Refresh Instant Swap before confirming Retry with backoff; if it persists, contact Quidax technical support