`res.type()`

Sets the Content-Type header from a MIME type or extension.

Since Express 4 Spec ↗

Syntax

res.type(type)

Parameters

Name	Type	Required	Description
`type`	`string`	Yes	A MIME type (`'application/json'`) or extension (`'png'`, `'html'`, `'txt'`).

Returns

Response — The response object, for chaining.

Examples

app.get('/data.csv', (req, res) => {
  res.type('csv').send('a,b\n1,2\n');
});

Output

Content-Type: text/csv; charset=utf-8

app.get('/raw', (req, res) => {
  res.type('application/octet-stream');
  res.send(Buffer.from([1, 2, 3]));
});

Output

Content-Type: application/octet-stream

Notes

Accepts shorthand extensions and looks them up via the `mime-types` database, adding a `charset` for text types automatically. Cleaner than `res.set('Content-Type', ...)`. Has no effect after the body is sent.