Blog
Postman collections versus browsers: why green API tests still fail under real CORS rules
Postman is not a web origin; it will not surface missing Access-Control-Allow-Origin that blocks SPAs.
1 min read
postmanapicors
Environment parity
Import the same base URL and auth headers your SPA uses; mismatched hosts hide CORS issues.
Document required preflight Allow-Headers in your OpenAPI description for both tools.
Team habits
Teach designers to validate flows in Chrome DevTools Network after Postman success.
Share saved HAR files when reporting bugs to backend teams.