Format
Controls the output properties of the image.
Adaptive filter &af
Use adaptive row filtering for reducing the PNG file size. This only works when the output image is png.
Base64 (data URL) &encoding=base64
Encodes the image to be used directly in the src= of the <img>-tag. Use this link to see the output result.
More info: Issue #59 - Return image base64 encoded.
//wsrv.nl/?url=wsrv.nl/lichtenstein.jpg&crop=100,100,720,530&encoding=base64Cache-Control &maxage=
Defines for how long an image should be cached by the browser. This will change the max-age of the Cache-Control HTTP-header.
We define a "far-future expiration" of 1 year by default. The duration can be specified in days, weeks, months, and years using the following suffixes:
d: daysw: weeks, 7 daysM: months, 30 daysy: years, 365 days
A duration must be in the range of 1d (1 day) to 1y (1 year), inclusive. Any other value will be ignored and fallback to the default value of 1 year.
More info: Issue #186 - Increase Cache-Control: max-age= to 1 year instead of 1 month.
//wsrv.nl?url=wsrv.nl/lichtenstein.jpg&w=100&maxage=31dCompression level &l=
The zlib compression level. Use a value between 0 (no Deflate) and 9 (maximum Deflate). The default value is 6. This only works when the output image is png.
Lossless compression &ll
Whether the resulting image should be lossless compressed. This only works when the output image is webp.
More info: Issue #386 - webP output is always lossy and cannot be requested as lossless.
Default image &default=
If there is a problem loading an image, then an error is shown. However, there might be a need where instead of giving a broken image to the user, you want a default image to be delivered.
More info: Issue #37 - Return default image if the image's URL not found.
The URL must not include a default querystring (if it does, it will be ignored).
Use &default=1 to redirect to the original URL specified in ?url=.
<img src="//wsrv.nl/?url=example.org/noimage.jpg&default=wsrv.nl/placeholder.svg">
Filename &filename=
To specify the filename returned in the Content-Disposition header. The filename must only contain alphanumeric characters.
More info: Issue #122 - Specify filename.
Interlace / progressive &il
Adds interlacing to GIF and PNG. JPEGs become progressive.
More info: Issue #50 - Add parameter to use progressive JPEGs.
<img src="//wsrv.nl/?url=wsrv.nl/lichtenstein.jpg&w=300&il">
Number of pages &n=
To select the number of pages to render. The default value is 1. Set to -1 to mean "until the end of the document".
TIP
-1 will be useful if you need to resize an animated WebP or GIF image.
<img src="//wsrv.nl/?url=wsrv.nl/banana.webp&h=300&output=gif&n=-1">
Output &output=
Encodes the image to a specific format. Accepts jpg, png, gif, tiff, webp or json. If none is given, it will honor the origin image format.
More info: Issue #62 - Format conversion.
<img src="//wsrv.nl/?url=wsrv.nl/lichtenstein.jpg&w=300&output=webp">
Page &page=
To load a given page (for an PDF, TIFF and multi-size ICO file). The value is numbered from zero. For a multi-resolution image, you can use -1 to get the largest page and -2 to get the smallest page.
Quality &q=
Defines the quality of the image. Use values between 1 and 100. Defaults to 80. This only works when the output image is jpg, tiff or webp.
<img src="//wsrv.nl/?url=wsrv.nl/lichtenstein.jpg&w=300&q=20">