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Make responsive image sizes and srcset code from one image

Upload one JPG, PNG, WebP or AVIF. You get resized copies, ready-to-paste <picture> HTML and a file-size list in one ZIP. Images are never enlarged or stretched.

or drop them here

JPG, PNG, WEBP, AVIF · Up to 5 images
Free account needed for your 3 free jobs a day

No file at hand? See the prepared example

Standard toolIncluded · 3 free jobs a dayFree: 3 jobs a dayPro: up to 200 jobs a day · €12.99/month or €89.99/year
  • JPG / PNG / WEBP / AVIF
  • Up to 5 images
Prepared result preview · fictional sample dataSynthetic 1,600 px product image
Source
Prepare four widths in WebP and JPEG
Measured interpretation
  • Widths: 320, 640, 960 and 1,280 px
  • Original is not enlarged
  • Stable source identities prevent equal-basename collisions

source-01-product-320w.webp · source-01-product-1280w.jpg · picture-markup.html · manifest.json

BringJPG, PNG, WEBP, AVIF
GetImage variants, picture HTML, bytes report and ZIP
PrivacyEncrypted source · 24-hour result

One clear job, from source to download

  1. 1

    Add the source

    Supported formats and limits are visible before the upload.

  2. 2

    Confirm the settings

    Review the exact source, options, units and access before processing.

  3. 3

    Inspect and download

    Check the preview and warnings, then unlock the complete package.

Making responsive image sizes and srcset markup

Your images go in

You upload JPG, PNG, WebP or AVIF images, up to 5 per run. You set the display width range you need, and the pack makes copies of each image at the widths in that range. Images are never enlarged or stretched. If a requested width is larger than the source, it is capped at the source width and any duplicate widths that result are removed. It is a standard tool, included in your 3 free jobs a day with a free account.

The ZIP and how to check it

You get one ZIP with the resized copies, ready-to-paste <picture> HTML and a file-size list for every variant. The srcset entries and width descriptors come from the files that were actually written, so a variant is never labelled with a width it did not reach. When two uploads share a name or differ only in case, each gets its own output files. Long names are shortened without losing the extension.

Formats, the 2x option and the sizes attribute

You choose WebP plus JPEG, or AVIF plus WebP plus JPEG. You can also add a 2x set for high-density screens. Each image produces a copy at every kept width in every chosen format, so the ZIP grows quickly. The sizes attribute depends on your layout. Making it match your real CSS stays your job, and the markup only works as intended once you have done that.

Questions before you run it

Will a small source image be upscaled to reach a requested width?

No. Widths above the decoded source size are clamped and the collapsed duplicates are removed. A variant is never labelled with a width the finished file did not reach.

Which output formats can the pack produce?

WebP plus JPEG, or AVIF plus WebP plus JPEG. Sources may be JPG, PNG, WEBP or AVIF.

What happens if two uploads have the same filename?

Each source is namespaced by its position in the upload order, so names that match or differ only in case still produce distinct output files. Unicode filenames keep their identity and overlong names are shortened without losing a valid extension.

Does the generated picture markup contain correct sizes?

The HTML carries srcset entries and width descriptors taken from the files that were actually written. The sizes attribute depends on your layout, so making it describe the real CSS is still your job.

How many images can one run handle?

Five per run. Each image produces a variant at every retained width in every selected format, plus the optional 2x DPR set, so the ZIP grows quickly.