New web-generated API keys default to Ed25519
Kalshi’s October 1 changelog says the website’s new-key dialog now selects Ed25519 by default. Existing keys are unchanged. RSA remains a choice for clients that need it.
The detail that can trip up a connection
Kalshi’s API-key guide says clients must sign using the algorithm that matches the key. A PEM header alone is not enough to identify that algorithm. The guide distinguishes the website default from the generation API, which still chooses RSA when key_type is omitted. API Keys guide.
What this means for setup
Our interpretation: “create a new key” is no longer a sufficiently precise instruction for a client that only supports RSA. The connection guide should name the supported key type, and the client should identify the parsed key’s algorithm.
Before replacing a working connection, check the client’s current documentation. In a test environment, verify a read request first. Keep private keys out of screenshots, support messages, browser code, and shared documents.
What we did not test
We did not create keys, connect a trading account, or test third-party clients. We cannot infer a particular product’s compatibility from Kalshi’s documentation alone.
Primary record: Kalshi API changelog, October 1 entry; API Keys guide. The distinction between a website default and an API default is explicit in both sources.
Kalshi Wire is an independent publication, not affiliated with or endorsed by Kalshi. Editorial information, not a trading recommendation.