Index symbols
Pass the index symbol. Case does not matter, and the^ prefix that many market data feeds use is optional, so SPX, spx, and ^SPX return the same logo. If you keep the prefix, URL-encode it as %5E.
How an index resolves
The CDN maps the symbol to the domain of the company that publishes the index, then returns that company’s logo. Indexes from the same publisher return the same logo. For example,SPX and DJI both return the S&P Global logo.
When a symbol matches no stock, a stock ticker lookup tries it as an index symbol, so /ticker/SPX returns the same logo as /index/SPX. If you know the symbol is an index, use /index/, because a stock with the same symbol takes priority on /ticker/.
An index symbol that Logo.dev does not know returns 400 Bad Request, not a monogram, whatever fallback is set to. See Errors.
For the other parameters, see the Logo CDN overview.