Batch Resize Images
Resize a whole folder of images at once. Four resize modes, output in the source format or JPG/PNG/WebP. Everything happens in your browser — no upload, no signup, no per-file limit.
Consumer cameras and smartphones shoot at their native resolution — a modern iPhone captures at 12 MP (4032 × 3024 px) and each JPEG lands at 5–10 MB. Fifty event photos can total 400 MB. E-commerce platforms like Shopify cap uploads at 4 MB per image; Squarespace still recommends keeping files under 500 KB for performance; email services routinely bounce attachments over 10 MB. Batch resizing brings an entire folder into range at once instead of processing files one by one.
The four resize modes cover the most common workflows. Percentage applies a uniform scale — 50% halves both dimensions and cuts file size by roughly 75%. Longest edge is the most versatile mode for mixed-orientation batches: it normalizes portrait and landscape photos to the same bounding box without stretching either, and it skips files that are already small enough. Exact width and exact height are for fixed-width galleries where every image must match one specific dimension precisely.
Output format defaults to matching the source, but switching to WebP saves an additional 25–35% over JPG at equivalent quality. If you need to hit a specific byte target after resizing, the image compressor can squeeze further without changing dimensions.
Drop multiple images to resize at once
Aspect-preserving · keep or change format · never uploaded
Common: 1080 (social), 1600 (web), 2048 (retina)
How batch resize works
Each image is decoded by the browser, redrawn onto a smaller canvas at the target dimensions, and re-encoded into your chosen format. ToolChop processes files sequentially so memory stays predictable — a 200-file batch just takes 200× as long as one, not 200× the memory.
Why a local batch resizer matters
Batch resizing is almost always a business workflow: prepping product photos, downsizing event photos before sharing, shrinking screenshots, generating client deliverable thumbnails. The volume of content makes the privacy stakes higher than for single files. ToolChop keeps the entire batch local.
Common target dimensions
- Social media — 1080 px longest edge
- Web body images — 1600 px longest edge
- Email attachments — 1024 px longest edge
- Retina display — 2048 px longest edge
- Thumbnails — 400–800 px longest edge
Frequently asked questions
How do I resize many images at once online for free?
Drop the whole folder (or as many files as you like). Pick a resize mode — Percentage, Longest edge, Exact width, or Exact height. Each file processes in your browser and a Save button appears beside it. Click Download All to save the entire batch. No account, no upload, no daily limit.
Does ToolChop upload my images?
No. Every resize happens in your browser using Canvas. None of the images leave your device. This matters more for batches than for single files — uploading 50 photos to a server is 50× the data exposure.
Why is the privacy story important for a batch resizer?
Batch resizing is almost always a business or personal-archive workflow: prepping product photos for an e-commerce listing, downsizing event photos before sharing with friends, shrinking screenshots for a support ticket, generating thumbnails for a client. The volume means more sensitive content travels in one shot if uploaded. ToolChop keeps the entire batch local.
What is the difference between the resize modes?
Percentage scales every image to N% of its original size (50% halves both dimensions). Longest edge sets the longest side to N pixels and scales the shorter side proportionally — keeps aspect ratio, skips files that are already smaller. Exact width forces every image to N pixels wide (height scales proportionally). Exact height forces every image to N pixels tall.
Which mode should I use?
Longest edge for mixed-orientation batches (mix of portrait and landscape) — preserves aspect ratio per file and skips images that are already small enough. Percentage when you want consistent relative downsize. Exact width/height when every output needs the same single dimension (rare; usually for fixed-width galleries).
Common target sizes?
Social media: 1080 px longest edge. Web body images: 1600 px longest edge. Email attachments: 1024 px longest edge. Retina display: 2048 px longest edge. Email-size thumbnails: 800 px longest edge. The Longest-edge mode handles all these cleanly.
Does the resizer preserve aspect ratio?
Yes for Scale and Longest-edge modes. Exact-width and Exact-height modes preserve aspect ratio along the other dimension (specify width → height scales proportionally). To produce non-aspect-preserving stretches, use a dedicated single-file resizer.
What output format options are available?
Match (keep each file's original format), JPG, PNG, or WebP. WebP at the same quality is typically 25–35% smaller than JPG — a great default for web. JPG is the most compatible. PNG is lossless and supports transparency.
Will the resizer make images larger?
Yes if you request a scale above 100% (Scale mode) or a longest-edge larger than the source. Canvas's bilinear upscaling is decent for small upscales but not for major ones. For high-quality upscaling, use a dedicated AI upscaler — ToolChop doesn't have one yet because no-upload AI upscaling requires heavyweight WebGPU models.
How long does a 100-image batch take?
Roughly 20–60 seconds on a modern laptop. Most of the time is decoding each source image; resizing itself is fast. The page processes files sequentially to keep memory predictable. You can leave the tab and come back — processing continues in the background.
What happens if one file fails?
The failed file is marked with an error icon and a short reason; the batch continues with the next file. You can remove the failed entry (× button) and re-drop a different one. ToolChop never aborts the whole batch because of one bad file.
Why use ToolChop instead of ImageMagick or XnConvert?
Two reasons. First, no install — ToolChop runs in any modern browser, on any OS, including Chromebooks and tablets where ImageMagick isn't available. Second, no upload, which uploaded batch resizers like Bulkresizephotos require. ImageMagick is great for power users; ToolChop is better when you want zero setup and zero data exposure.