// mime type · application type
application/vnd.openxmlformats-officedocument.spreadsheetml.sheet
Excel spreadsheet · .xlsx
What application/vnd.openxmlformats-officedocument.spreadsheetml.sheet is
This long type is a modern Excel spreadsheet (.xlsx). The vnd.openxmlformats-officedocument family covers Office Open XML documents — verbose, but exact type matching is what makes downloads open in the right app.
How it's used
You'll see this as a Content-Type value on requests and responses — for example Content-Type: application/vnd.openxmlformats-officedocument.spreadsheetml.sheet. It's the type associated with the .xlsx file extension. Application types cover structured data and binary formats — from JSON and XML to PDFs, archives, and Office documents.
Other application types
application/json application/ld+json application/xml application/javascript application/pdf application/zip application/gzip application/octet-stream application/x-www-form-urlencoded application/wasm application/vnd.openxmlformats-officedocument.spreadsheetml.sheet application/vnd.openxmlformats-officedocument.wordprocessingml.document