FAQ - API Usage

I receive an error when making a REST API request.

If an error occurs during a REST API request, an error code is included in the HTTP response body. The main error codes can be found on the REST API Usage and Error Guide page and in the response examples shown at the bottom right of each API Reference page. If you encounter an error that is not documented and cannot identify its cause, please contact us with the error code included in your inquiry.

“Invalid parameter. Check the given value!” Error Despite Correct Inputs

This error may occur if the parameter includes special characters such as : or + (commonly found in date formats) and the query string is sent without URL encoding. Please refer to the REST API Usage and Error Guide page or the Make Your First Upbit API Call page, and ensure that URL encoding is applied before making the request.

What is URL Encoding?

URL encoding is an encoding method that converts characters that cannot be included in a URL within a communication protocol into transmittable characters. Target characters, including special characters, are converted during encoding into a string consisting of a percent sign (%) followed by two hexadecimal digits.

(Example) : is encoded as %3A and + is encoded as %2B.

I added my current IP address to the API Key’s allowed IP list, but I still get an error.

This can happen if the IP address shown on your local network differs from the one actually used for external communication.

For local PC environments: Use a search engine (e.g., Google) to look up “what is my IP” or “my IP address,” and register the IP address displayed.
**For server environments: Register the server’s external/public IP address used for outbound communication.

Once the correct address is added to the allowed IP list, please try your request again.

Can I use the API in a dynamic IP environment?

No. Exchange APIs that require API Key authentication must be used only after registering a static (fixed) IP address in the allowed IP list. Since these APIs involve sensitive actions such as deposits, withdrawals, and trading, this policy is in place to protect your assets. If you are on a dynamic IP, please use a cloud server or a static IP service for secure access.

I get a certificate error (SSL: CERTIFICATE_VERIFY_FAILED).

Please update your local environment’s root certificates to the latest version.

Windows: Apply the latest system updates.
macOS: Apply the latest system updates.
Linux: apt-get install ca-certificates

My requests used to work, but recently I am seeing more frequent errors.

This is often caused by DNS cache issues. We recommend clearing the DNS cache in your local environment:

Windows: ipconfig /flushdns

I am getting a CORS error.

When sending REST API or WebSocket requests for quotation data with an Origin header, the request rate limit is restricted to 1 request per 10 seconds.

Read the related announcement
If this policy is applied, the Remaining-Req response header will include group=origin.
If your requests exceed this limit, a CORS error may occur.
If you need to make browser-based requests, please keep within the limit or use a proxy server.