Batch Resize Images — Resize Multiple Images at Once

Select many photos at once, apply one set of resize/convert settings, and download a single ZIP. Ideal for social packs, product shots, or cleaning a folder of exports.

How to batch resize images in five steps

1. Add all your images at once. Use Select Image(s) to pick multiple files, or drag and drop a whole group onto the upload area. Every file is read directly by your browser — nothing is uploaded to a server.
2. Choose how the resize is calculated. Scale by percentage (for example 50%) or set exact dimensions in pixels. Percentage is the fastest option when your source files are different sizes but all need the same relative shrink.
3. Pick the fit behavior. With exact dimensions, decide what happens to images that do not match that shape: fit them inside the box (nothing cropped, nothing distorted) or fill and crop (uniform sizes, edges trimmed). Avoid stretching — it distorts faces, products, and text.
4. Set format and quality once. The same output format, quality, and optional crop apply to every file in the batch. If you cropped the preview image, you can apply that same crop to all files — handy for product shots that need identical framing.
5. Process and download everything as a ZIP. Click Process & Download All as ZIP. The tool works through the queue file by file and hands you a single archive with all the resized images, ready to upload or share.

Percentage vs. exact dimensions: which should you pick?

Percentage scaling is the right default for most batches. Setting 50% halves every image regardless of its starting size, so a mixed folder of phone photos and camera exports all shrink proportionally and every aspect ratio is preserved automatically. It is ideal for preparing a gallery, shrinking a folder before backup, or cutting upload sizes for a website.

Exact dimensions are for when the destination demands a specific size: a marketplace that wants 2000 px on the long edge, a banner slot that is exactly 1600×900, or thumbnails at 400×400. When sources have different aspect ratios, exact dimensions need a fit rule — otherwise some images come out distorted or inconsistently sized.

Handling mixed orientations and aspect ratios

Real batches are messy: portrait phone shots mixed with landscape exports, squares from social media next to panoramas. Two fit modes handle this:

• Fit inside. Each image is scaled so the whole picture fits within your target box, keeping its aspect ratio. Nothing is cropped and nothing is distorted — but the output files will have different pixel dimensions from each other.
• Fill and crop. Each image is scaled to cover the target box completely, then the overflow is trimmed away. Every output has identical dimensions, which is what you want for grids, carousels, and thumbnails — at the cost of losing some edge content.

Cropping is a content decision: for product photos, run a small test batch and check the framing before processing hundreds of files.

File naming and the ZIP download

Batch tools are only useful if you can find the results afterward. Output files keep their original names, so product-014.jpg comes back as product-014.jpg — resized, not renamed. When you change the format (say JPG to WebP), only the extension updates to match.

The ZIP option packs every processed file into a single archive — browsers may throttle dozens of individual downloads, while one ZIP always works. Unzip it into a fresh folder and spot-check a few images before replacing your originals.

Practical limits: browser memory and very large batches

Because everything runs locally, your device's memory is the ceiling. Each image is decoded to full pixels while it is processed — a single 24 MP photo can briefly use hundreds of megabytes. Batches of 20–50 typical photos run fine on most machines; several hundred large exports in one go can slow the tab down or, on low-memory devices, crash it.

If a batch feels sluggish:

• Split it into smaller groups of 30–50 files and run them one after another.
• Close heavy tabs and apps before starting a big run.
• Resize before converting formats — fewer pixels means less memory at every later step.
• On phones and tablets, keep batches small; mobile browsers are stricter about memory.

Mistakes that waste a batch run

• Upscaling small images. Enlarging an 800 px image to 2000 px does not add detail — it just makes a bigger, blurrier file. Batch resize is for shrinking; only upscale when you have no alternative.
• Stretching mixed aspect ratios into one size. Forcing portraits and landscapes into the same rectangle without cropping stretches everything. Use fit-inside or fill-and-crop instead.
• Converting transparency to JPG. JPG has no alpha channel. Batch-converting PNG logos with transparent backgrounds to JPG fills the transparency, usually with black or white. Keep PNG or WebP for anything transparent.
• Recompressing already-compressed originals. If your sources are heavily compressed JPGs, keep quality at 85 or above for the batch, or the artifacts will stack up across hundreds of files.

Frequently asked questions

How many images can I resize at once?

There is no fixed cap — the practical limit is your device's memory. Most desktops handle 30–50 photos per batch comfortably; very large batches are better split into smaller groups.

Are my images uploaded to a server?

No. The entire batch is processed locally in your browser. Files never leave your device, which is also why there is no upload wait and no queue.

Will the resized files keep their original names?

Yes. Output files keep the original file names, with only the extension updated if you change format — so they stay matched to your catalog, SKUs, or gallery order.

Can I resize and convert the format in the same batch?

Yes. Set the output format once — for example WebP — and every resized image is converted as it is processed. One run, one ZIP, done.

Why did my browser slow down during a large batch?

Each image is decoded into memory while it is processed, and hundreds of large photos add up. Split the batch into smaller groups and close other heavy tabs; the tool continues fine with the next group.