application/*
application/wasm
File extensions: .wasm
WebAssembly binary module — near-native code for the web.
What is application/wasm?
application/wasm is the media type for WebAssembly binary modules. Setting it correctly is required for the browser's streaming compilation via WebAssembly.instantiateStreaming — with a wrong type the browser falls back to slower path.
Typical usage
Games, image/video processing, cryptography libraries, ports of C/C++/Rust code.
Common gotchas
If you serve .wasm files without this type (e.g. as application/octet-stream), instantiateStreaming throws a TypeError. Configure your server to map .wasm → application/wasm.
HTTP header example
Response header
Content-Type: application/wasm; charset=utf-8Reference
W3C WebAssembly
Frequently asked questions
What is the application/wasm MIME type?
application/wasm is the media type for WebAssembly binary modules. Setting it correctly is required for the browser's streaming compilation via WebAssembly.instantiateStreaming — with a wrong type the browser falls back to slower path.
What file extension does application/wasm use?
Files served as application/wasm typically use the extension .wasm. The most common is .wasm.
How do I set the Content-Type for application/wasm?
Send the HTTP response header Content-Type: application/wasm; charset=utf-8. Games, image/video processing, cryptography libraries, ports of C/C++/Rust code.
Is application/wasm an official MIME type?
Yes. application/wasm is officially registered with IANA (W3C WebAssembly), so standards-conformant clients recognize it.
What are common mistakes with application/wasm?
If you serve .wasm files without this type (e.g. as application/octet-stream), instantiateStreaming throws a TypeError. Configure your server to map .wasm → application/wasm.