API Integration

Debugging "Invalid Signature" Errors

Jan 11, 2026 1,188 Views

90% of signature errors are caused by extra whitespace in the raw body string. Trim it!

payload.js

body.trim()

@Finovo_Dev_Rel Jan 11, 17:50

Regarding the whitespace debug: I wrote a small middleware to auto-trim raw bodies before the HMAC check. Saves a lot of headache!