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Transform videos

You can optimize and manipulate videos stored outside of Cloudflare Stream with Media Transformations. Transformed videos and images are served from one of your zones on Cloudflare.

To transform a video or image, you must enable transformations for your zone. If your zone already has Image Transformations enabled, you can also optimize videos with Media Transformations.

You can dynamically optimize and generate still images from videos that are stored outside of Cloudflare Stream with Media Transformations.

Cloudflare will automatically cache every transformed video or image on our global network so that you store only the original image at your origin.

To enable transformations on your zone:

1. In the Cloudflare dashboard, go to the Transformations page.

   Go to Transformations ↗

2. Locate the specific zone where you want to enable transformations.

3. Select Enable for the zone.

You can convert and resize videos by requesting them via a specially-formatted URL, without writing any code. The URL format is:

https://example.com/cdn-cgi/media/<OPTIONS>/<SOURCE-VIDEO>

• example.com: Your website or zone on Cloudflare, with Transformations enabled.
• /cdn-cgi/media/: A prefix that identifies a special path handled by Cloudflare's built-in media transformation service.
• <OPTIONS>: A comma-separated list of options. Refer to the available options below.
• <SOURCE-VIDEO>: A full URL (starting with https:// or http://) of the original asset to resize.

For example, this URL will source an HD video from an R2 bucket, shorten it, crop and resize it as a square, and remove the audio.

https://example.com/cdn-cgi/media/mode=video,time=5s,duration=5s,width=500,height=500,fit=crop,audio=false/https://pub-8613b7f94d6146408add8fefb52c52e8.r2.dev/aus-mobile-demo.mp4

The result is an MP4 that can be used in an HTML video element without a player library.

Specifies the kind of output to generate.

• video: Outputs an H.264/AAC optimized MP4 file.
• frame: Outputs a still image.
• spritesheet: Outputs a JPEG with multiple frames.
• audio: Outputs an AAC encoded M4A file.

Specifies when to start extracting the output in the input file. Depends on mode:

• When mode is spritesheet, video, or audio, specifies the timestamp where the output will start.
• When mode is frame, specifies the timestamp from which to extract the still image.
• Formats as a time string, for example: 5s, 2m
• Acceptable range: 0 – 10m
• Default: 0

The duration of the output video or spritesheet. Depends on mode:

• When mode is video or audio, specifies the duration of the output.
• When mode is spritesheet, specifies the time range from which to select frames.
• Acceptable range: 1s - 60s (or 1m)
• Default: input duration or 60 seconds, whichever is shorter

In combination with width and height, specifies how to resize and crop the output. If the output is resized, it will always resize proportionally so content is not stretched.

• contain: Respecting aspect ratio, scales a video up or down to be entirely contained within output dimensions.
• scale-down: Same as contain, but downscales to fit only. Do not upscale.
• cover: Respecting aspect ratio, scales a video up or down to entirely cover the output dimensions, with a center-weighted crop of the remainder.

Specifies maximum height of the output in pixels. Exact behavior depends on fit.

• Acceptable range: 10-2000 pixels

Specifies the maximum width of the image in pixels. Exact behavior depends on fit.

• Acceptable range: 10-2000 pixels

When mode is video, specifies whether or not to include the source audio in the output.

• true: Includes source audio.
• false: Output will be silent.
• Default: true

When mode is audio, audio cannot be false.

If mode is frame, specifies the image output format.

• Acceptable options: jpg, png

If mode is audio, specifies the audio output format.

• Acceptable options: m4a (default)

Specifies the filename to use in the returned Content-Disposition header. If not specified, the filename will be derived from the source URL.

• Acceptable values:
  • Maximum of 120 characters in length.
  • Can only contain lowercase letters (a-z), numbers (0-9), hyphens (-), underscores (_), and an optional extension. A valid name satisfies this regular expression: ^[a-zA-Z0-9-_]+.?[a-zA-Z0-9-_]+$.
• Examples: default.mp4, shortened-clip_5s

• Input video must be less than 100MB.
• Input video should be an MP4 with H.264 encoded video and AAC or MP3 encoded audio. Other formats may work but are untested.
• Origin must support either HTTP HEAD and range requests, and must return a Content-Range header.

• Maximum input file size is 100 MB. Maximum duration of input video is 10 minutes.
• Media Transformations are not compatible with Bring Your Own IP (BYOIP).
• Input video should be an MP4 with H.264 encoded video and AAC or MP3 encoded audio, or animated GIF. Other formats may work but are untested.

When using Media Transformations from a Cloudflare Worker, we recommend using the bindings. Otherwise, if the Worker is calling Media Transformations on the same zone used as its trigger, apply the global_fetch_strictly_public compatibility flag to avoid 404 errors on /cdn-cgi/media paths.

After November 1st, 2025, Media Transformations and Image Transformations will use the same subscriptions and usage metrics.

• Generating a still frame (single image) from a video counts as 1 transformation.
• Generating an optimized video or extracting audio counts as 1 transformation per second of the output content.
• Each unique transformation, as determined by input and unique combination of flags, is only billed once per calendar month.
• All Media and Image Transformations cost $0.50 per 1,000 monthly unique transformation operations, with a free monthly allocation of 5,000.