Format
Control the output properties of the image.
Adaptive filter &af
Use adaptive row filtering for reducing the PNG file size. This is only supported for the png format.
Base64 (data URL) &encoding=base64
Encode 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=
Specify how long the browser should cache the image by setting the max-age directive 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
The duration must be between 1d (1 day) to 1y (1 year), inclusive. Values outside this range will be ignored and default to 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 is only supported for the png format.
Lossless compression &ll
Enable lossless compression for the output image. This is only supported for the jxl, tiff and webp formats.
More info: Issue #386 - webP output is always lossy and cannot be requested as lossless.
Default image &default=
If an image fails to load, an error is shown by default. However, you may prefer to display a fallback image instead of showing a broken image to the user.
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=
Specify the filename returned in the Content-Disposition header. The filename must contain only alphanumeric characters.
More info: Issue #122 - Specify filename.
Interlace / progressive &il
Add 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=
Select the number of pages to render. Defaults to 1. Set to -1 to render all pages 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=
Encode the image to a specified format. Accepts jpg, jxl, png, gif, tiff, webp or json. If no format is provided, it defaults to 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=
Load a specific page from a multi-page or multi-resolution input (GIF, WebP, TIFF, PDF, ICO). Use a zero-based index. For multi-resolution images, use -1 to load the largest page and -2 to load the smallest.
Quality &q=
Set the quality of the image. Use values between 1 and 100. Defaults to 80. This is only supported for the jpg, jxl, tiff and webp formats.
<img src="//wsrv.nl/?url=wsrv.nl/lichtenstein.jpg&w=300&q=20">