Open Tools LibraryOpen Tools Library
Image Tools

Image Resizer

Resize photos and images by percentage or exact pixels — never stretched.

Also known as: Photo resizer, Picture resizer, Bulk image resizer

100% FreeNo Signup RequiredFiles Never UploadedBatch Resizing
100% local — nothing you enter here ever leaves this browser tab
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Step by step

How it works

  1. 1Upload one or more images — JPG, PNG, WEBP, and most other formats work.
  2. 2Choose "By percentage" to scale relative to the original size, or "Exact dimensions" to set a specific width and height.
  3. 3Leave aspect ratio locked to avoid distortion, or unlock it if you deliberately want a different ratio.
  4. 4Click Resize — a single image downloads directly, and multiple images download together as a ZIP.
Why OTL

Why use Image Resizer

Never stretched or squeezed

Aspect ratio is locked by default, so resized images always keep their original proportions.

Two resize modes

Scale by a percentage of the original size, or set an exact pixel width and height.

Batch-aware, not batch-blind

Resizing multiple images with different proportions calculates each one's height from its own ratio, not a one-size-fits-all box.

High-quality scaling

Uses your browser's high-quality image smoothing, not a naive pixel-doubling resize.

ZIP download for batches

Resize a whole folder of images at once and get a single ZIP file back instead of dozens of separate downloads.

Nothing uploaded

Every image is decoded and resized locally in your browser tab.

Real-world use

Who uses Image Resizer

Meeting an upload size limit

Shrink a photo's dimensions before uploading it to a form or portal that rejects large images.

Preparing product photos

Resize a batch of product shots to match the exact dimensions a marketplace template requires.

Fitting a banner or thumbnail slot

Resize an image to exact pixel dimensions for a website banner, social post, or thumbnail.

Shrinking phone photos

Scale down a full-resolution phone photo before emailing or messaging it.

Batch prep for a gallery

Resize dozens of photos to a consistent width before uploading them to a website gallery.

Creating smaller previews

Generate a smaller version of an image to use as a lightweight preview or placeholder.

Deep dive

About Image Resizer

Resizing an image sounds trivial until you actually need to do it — a form that rejects anything over 2000px wide, a photo that needs to fit a specific banner slot, or a batch of product photos that all need to match a template's dimensions exactly. Doing this one image at a time in a desktop editor works, but it's slow for anything more than a couple of files, and most "resize image" websites make you upload your photos to a server first.

This tool works two ways. Percentage mode scales every image relative to its own original size — useful when you just want everything "half as big" without calculating exact numbers. Exact dimensions mode lets you type a target width and height directly; with aspect ratio locked (the default), changing the width automatically recalculates the height to match the original photo's proportions, so you can never accidentally distort an image by typing mismatched numbers.

Batch mode is genuinely batch-aware, not just a loop that repeats one setting blindly. When you resize several images at once with aspect ratio locked, each image's height is recalculated from its own original proportions — not forced to match the first image's ratio — so a mix of portrait and landscape photos all come out correctly proportioned instead of some of them getting stretched to fit a one-size-fits-all box.

Everything runs through your browser's own image decoding and canvas rendering — the same engine used to display images on any web page — so there's no upload step and no server-side queue. Add your images, set a target size, and download the result (or a single ZIP file if you resized more than one) in seconds.

Compare

Image Resizer vs. other options

How Open Tools Library compares to desktop software and other online tools.

FeatureOpen Tools LibraryDesktop softwareOther online tools
PriceFree, unlimitedOften paid or subscriptionOften free with daily limits
InstallationNoneRequiredNone
File privacyNever leaves your deviceStays localUploaded to a server
Batch resizingYes, with per-image aspect handlingVaries by appOften one image at a time
SpeedInstant, on-deviceFastDepends on upload + server queue
WatermarksNeverNeverSometimes on free tiers
Pro tips

Pro tips

  • Percentage mode is the fastest way to shrink an image without doing any math — 50% halves both dimensions.
  • In exact dimensions mode, leave aspect ratio locked and just set the width — the height is calculated automatically to avoid distortion.
  • When resizing a batch of mixed portrait and landscape photos, exact-dimensions mode with aspect ratio locked uses each image's own width as the target and adjusts height per image, so nothing gets stretched.
  • Enlarging an image beyond its original size will look softer — resizing works best for shrinking, since no resize tool can add detail that wasn't in the original.
  • JPEGs stay JPEG-quality after resizing; other formats are kept in a lossless format so quality isn't lost in the resize step itself.
Under the hood

Technical specs

Supported input
.jpg, .jpeg, .png, .webp, .gif, .bmp, and more
Resize modes
Percentage or exact pixel dimensions
Aspect ratio
Locked by default, per-image in batch mode
Batch output
ZIP file when resizing more than one image
Image count
No enforced limit (device memory dependent)
Processing location
100% local, in your browser

Privacy & security

Photos you're resizing often aren't meant for public upload in the first place — so where the resizing actually happens matters.

Each image is decoded and resized locally — never uploaded, never seen by a server.

No account, no email, no login — just images in, resized images out.

Nothing is retained after your download finishes; there's no copy waiting on a remote server.

Equally private whether you're resizing a single photo or a batch of hundreds.

FAQ

Frequently asked questions

Is my image uploaded to a server?

No. Every image is decoded and resized entirely in your browser — nothing is ever uploaded.

Will resizing distort my image?

Not with aspect ratio locked (the default) — width and height are always scaled together, so proportions are preserved.

Can I resize multiple images at once?

Yes. Add as many images as you like and resize them all in one action — you'll get a ZIP file if you resized more than one.

What image formats are supported?

JPG, PNG, WEBP, GIF, BMP, and most other formats your browser can display.

Can I make an image bigger, not just smaller?

Yes, using either percentage values over 100% or exact dimensions larger than the original — though enlarging beyond the source resolution will look softer, since no detail is added.

Is there a limit on image size or count?

No hard limit — very large images or batches just take a little longer since everything processes on your device.

Stuck?

Troubleshooting

My resized image looks blurry

This usually happens when enlarging an image beyond its original size — no resize can invent detail that wasn't captured originally. Try shrinking instead, or start from a higher-resolution source.

The height field is disabled

That's expected with aspect ratio locked — height is calculated automatically from the width to prevent distortion. Turn off the lock if you need to set both independently.

My batch of images came out different sizes

That's intentional with aspect ratio locked: each image's height is calculated from its own original proportions relative to your target width, so a mix of portrait and landscape photos all stay correctly proportioned instead of being forced into identical dimensions.

One image in my batch failed

The file may be corrupted or in a format your browser can't decode. Try opening it in an image viewer first to confirm it's valid.

Ready to use Image Resizer?

Free, private, and ready right now — no signup required.

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