Image Tools

Image Comparison Slider

Compare two images with a sliding before-and-after view. Drag the divider, switch directions or swap images, then save the current comparison as a PNG. Everything stays in your browser.

Your content stays on your device Free, with no account
Two images. One sliding view. Local comparison · no uploads

No file selected.

No before image selected.

No file selected.

No after image selected.

Static PNG, JPEG or WebP · each up to 20 MiB, 40 MP and 16,384 px per side. Browser orientation applies.

Drag across the preview or use this slider. Arrow keys adjust the slider; Home and End show either image.

The before image sets the preview shape. Both images fit inside it without cropping or stretching; different proportions create empty space. Swap to change the frame. Use matching dimensions and alignment for the closest visual comparison.

YOUR BEFORE / AFTER COMPARISON

Choose both images to reveal the comparison.

Ready. Choose a before and an after image.

The PNG saves the current split at the displayed preview’s pixel dimensions (up to 1,200 × 800). The divider and controls are excluded. Empty areas remain transparent. This is a visual comparison, without automatic difference scoring or original-resolution export.

Want both images in one grid? Try the Image Collage Maker.

A FEW SIMPLE STEPS

How to use Image Comparison Slider

  1. Choose or drop one before image and one after image in their labeled boxes.
  2. Drag across the preview or adjust the comparison position slider. Its arrow keys, Home and End also work.
  3. Choose left/right or top/bottom comparison. Swap images or center the divider as needed.
  4. Download the current split as a PNG at the reported preview resolution, or clear both images.
PRIVATE BY DESIGN

Why use this tool?

Your images are never uploaded to any server; decoding, comparison and PNG export run locally in your browser. No account or image history is required. Both images keep their proportions, and the shared preview makes it easy to inspect edits, compression or resizing results side by side.

Tool inputs stay in your browser. Only your theme preference is saved on this device.

A few things worth knowing

What if my images have different dimensions?

The before image sets the preview aspect ratio. Each image is centered and fitted inside that frame without cropping or stretching, so different proportions leave empty transparent space. Swapping images changes which image sets the frame. This tool does not align image features automatically; matching dimensions and framing give the clearest comparison.

Can I use the slider on a phone or with a keyboard?

Yes. Drag anywhere in the comparison area using a pointer or touch, or use the labeled position slider. Arrow keys adjust its value, and Home or End reveals an entire image. Left/right shows before on the left; top/bottom shows before on top.

What does the download contain?

A PNG of the current split without the interactive divider or controls. The preview is bounded to 1,200 pixels wide and 800 pixels high, never enlarged beyond the before image. Its actual pixel dimensions are reported. It is a raster comparison export, not an original-resolution or interactive HTML download. Empty areas remain transparent, and browser-decoded colors may differ from source-file values.

Which files can I compare?

Two static PNG, JPEG or WebP images, each up to 20 MiB, 40 megapixels and 16,384 pixels per side. Browser orientation is applied. Detected animated PNG/WebP, SVG, GIF, HEIC and AVIF are unsupported. Browser memory limits may be lower. Export is limited to 8 MiB.

Does the tool calculate a difference score?

No. It is a visual comparison slider, without pixel-difference scoring, AI analysis, automatic alignment or image editing. A visual similarity does not prove that files are identical.

Are images saved anywhere?

No input images are stored in browser storage or sent to a server. Replacing an image closes the previous bitmap; Clear and leaving the page release application-held images and output URLs. Pending decodes or PNG exports from cleared or replaced images are discarded.