mockstack.

Image Converter

BATCH · EMPTY ← Images & Media
No image selected
Add images to see them hereDrop them anywhere on the page, or use Add Images.
HEIC, PNG, JPEG, WebP, AVIF, GIF, and more.
READY RUNS LOCALLY

About the Image Converter

Converts, resizes, and compresses images in your browser, one file or a whole folder at a time. Add images, choose the output, and every image is converted as you change a setting; preview any of them before and after, then download one or all.

Every Setting

Add Images
Click Add Images, drop files anywhere on the page, choose a folder to add every image inside it, or paste from the clipboard. Phone formats like HEIC are read and converted, and sideways phone photos come out upright.
Format
PNG keeps transparency and exact pixels. JPEG is smallest for photos. WebP does both jobs well on the web, and AVIF is smaller still where the browser can write it. GIF, BMP, TIFF, and ICO are there for older software, print, and Windows icons; ICO holds every standard icon size up to 256 px.
Quality
The size-versus-fidelity dial for JPEG, WebP, and AVIF, from 10 to 100, with a box for an exact value. It starts at 100.
PNG Colors
All keeps every pixel exactly as it was, and still packs the file tighter than the browser would. 256, 64, and 16 reduce the image to that many colors, smoothed with dithering, which makes files much smaller. Screenshots, icons, and flat graphics often look the same; photos can show banding.
Resize
Original keeps each image’s size. Longest Side shrinks anything longer than the number you set and leaves smaller images alone. Width & Height starts at the selected image’s size; with Keep Proportions on, typing one side fills in the other, and every image keeps its own shape at that side. With it off, choose Fit Inside to keep the whole image in the box, Fill and Crop to fill the box and trim the overflow evenly, or Stretch to fill it exactly. Percent starts at 100%; drag the slider or type an exact value.
Metadata
Remove All leaves camera details, dates, and location out of the new files. Keep carries everything the original holds, location included. Edit lets you set author, copyright, and description for every image, and choose whether to keep the date taken, the camera details, and the location. JPEG, PNG, WebP, and TIFF hold metadata; GIF, BMP, ICO, and AVIF files come out without it.
File Names
A pattern for the new names: {name} is the original name and {n} numbers the batch.
Preview
Side by Side shows the original and the new version at their real relative size, so a smaller version looks smaller, and marks what Fill and Crop trims. Compare lays them over each other at the same size with a divider to drag, for checking quality. Under the preview is what the file carries: camera, date taken, author, and location.
Images
Every image with its size before and after. Click one to preview it, use the arrow to download it on its own, or Download All for a ZIP of every file.

Common Questions

How do I make a PNG smaller?
Choose PNG, then 256 under PNG Colors. Screenshots and graphics often drop to a third of their size with no visible change. All keeps every pixel and still trims what it can.
How do I resize to an exact size?
Under Resize, choose Width & Height and type the width. To set both sides independently, turn off Keep Proportions, type both, and pick how the image fits.
Does converting remove location data?
Yes, while Metadata is set to Remove All, which is the default. Keep and Edit show a file’s location under the preview when it has one.
Why is my photo sideways everywhere?
Phones store rotation as a metadata note. Anything that ignores the note shows the raw sideways pixels; converting here turns the pixels themselves upright.

Related: HEIC on Windows, Photo Editor, Background Remover.