Convert
Resize images to exact dimensions
Resize images to an exact width, height, or percentage, keeping the aspect ratio, entirely on your device.
For the best results: In the width, height, and percentage modes the aspect ratio is preserved, so nothing distorts.
Advanced settingsoptional, defaults work well
Processed entirely in your browser, your photos are never uploaded, logged, or stored.
What is Image Resizer?
Image Resizer is a free file converter that resizes images to an exact width, height, or percentage while keeping the aspect ratio, locally. Each image is decoded and re-encoded by your own browser's graphics engine, so your photos are never uploaded to a server. There is no queue, no watermark, and no account to create, and it keeps working with your connection off.
- ✦Runs entirely in your browser. Nothing you enter is ever uploaded
- ✦No account, no sign-up, and no data leaves your device
- ✦Works offline once the page has loaded
See it in action
A marketplace wants exact 500 x 500 product shots, but the studio photos are 1600 x 1200.
What you drop in
product.jpg (1600 x 1200), mode "Exact width x height", 500 x 500, fit "Fill & crop"
What you get
product-500x500.jpg at exactly 500 x 500 pixels, center-cropped so the product fills the square with no letterboxing and no distortion.
Tip: Pick the fit mode by what you can tolerate: Fill & crop trims the edges, Fit inside letterboxes onto a background, Stretch distorts. Percentage mode also upscales, 200% on a 800 x 600 image gave exactly 1600 x 1200 in testing.
Use cases
What people use it for
Scale a logo to the exact pixel dimensions a directory or profile form insists on.
Shrink a batch of photos to 25 percent for quick-loading thumbnails on a gallery page.
Fit a desktop wallpaper or channel banner to a precise width without opening a heavyweight editor.
Who uses Image Resizer?
Social media managers
produce each platform's required image dimensions from one master graphic without paying for a design suite subscription
Teachers and tutors
shrink oversized photos so worksheets and slide decks stay small enough to share through the school portal
App developers
generate assets at exact pixel sizes for stores and interfaces, keeping pre-launch screenshots off outside servers
How it works
- 1Choose your files. They open in your browser, not on a server.
- 2Your device converts, compresses, or resizes them locally, with no upload.
- 3The converted files download straight back; nothing is kept anywhere.
Tips for the best results
- Resize copies and guard the full-resolution original; you cannot get discarded pixels back.
- For platform specs, match the required longest edge first and let the other side follow.
- Apply one percentage across a whole batch to keep a photo set visually consistent.
- Avoid large enlargements; find a bigger source image instead of scaling a small one up.
- If you also plan to compress, resize first so the compressor works on fewer pixels.
FAQ
Frequently asked questions
What does keeping the aspect ratio actually do?
Aspect ratio is the relationship between width and height. With the ratio kept, entering one dimension automatically calculates the other in proportion, so a landscape photo stays landscape and faces do not stretch or squash. Break that proportion and the image distorts, which is the classic mistake behind oddly flattened profile pictures. This tool preserves the ratio for you by default.
Can I make a small image bigger without it going blurry?
Only up to a point. Enlarging cannot invent detail that was never captured; the resizer interpolates, spreading existing pixels across a larger area, which is why big enlargements look soft. Modest increases usually pass unnoticed, but doubling and beyond visibly degrades. Whenever possible, go back to the largest original you have and resize down from that instead.
Do my pictures leave my computer while resizing?
They do not. The pixel arithmetic runs on a canvas inside your own browser tab, so the image data has no reason to travel anywhere. Once the page has loaded you could disconnect from the internet entirely and keep resizing. Contrast that with typical resize websites, which quietly ferry every photo to their servers and back.
Should I resize by pixels or by percentage?
Use exact pixels when a platform dictates the target, such as a banner slot, a form field, or an avatar requirement, because you will land precisely on spec. Use percentage when shrinking a batch proportionally, for example halving everything from a photo shoot, since each image scales relative to its own original dimensions and the whole set stays consistent.
Does resizing an image reduce its quality?
Scaling down discards pixels, but done once from a good original it looks perfectly crisp, because remaining pixels are recalculated smoothly from the source. Quality problems creep in through repetition: resizing an already-resized JPG re-encodes it and compounds the loss each round. Keep one master file and produce every size you need directly from it.
What is the difference between resizing and cropping?
Resizing changes the dimensions of the whole image while keeping everything in frame, so nothing is removed, just scaled. Cropping cuts away part of the picture entirely, changing the composition. If a platform wants a different shape rather than a different size, cropping is the answer; if it wants smaller, resize.
Does resizing an image reduce its file size?
Dramatically, yes. File size grows with the number of pixels, and pixels grow with the square of the dimensions, so halving width and height leaves roughly a quarter of the data. Resizing is usually the single most effective way to lighten a photo, well ahead of fiddling with compression settings alone.
How do I resize a photo without stretching it?
Change only one dimension and let the other follow automatically. Stretching happens when width and height are forced to new values that break the original proportions. With the aspect ratio locked, this tool computes the matching second dimension for you, so people and objects keep their natural shape at any size.
Are there any usage limits?
None. Everything is generated locally in your browser, so there is no server cost, no metering, and no daily cap, use it as many times as you like, completely free.
Also useful
Related free tools
More Convert tools
