Resize images online: pixels, percentage or social media presets
Whether you are preparing a photo for a website, shrinking a screenshot for an email or making a cover image for a social network, you need to change an image's dimensions. This free image resizer does it in your browser in a couple of clicks. Enter the exact width and height in pixels, scale the image by a percentage, or choose a ready-made size for Instagram, YouTube, Facebook, LinkedIn and X. Your photos are never uploaded; the work is done by your own device.
The tool handles JPG, PNG, WebP, GIF and BMP files, processes many pictures in one batch and shows a live preview of the result before you commit. You can also crop, rotate and mirror at the same time, then download everything as a ZIP archive.
How to resize an image
- Drop your pictures onto the box above or click Choose images. The original dimensions appear next to each file.
- Pick a method: Pixels for exact width and height, Percentage to scale proportionally, or Preset size for social networks.
- If you give both width and height, decide whether the picture should fit inside the box, be cropped to fill it, or be stretched. Rotate or mirror it if needed.
- Check the preview line, which shows before and after dimensions, then press Resize images.
- Download single files, or use Download all (ZIP). The new dimensions are added to each file name.
Fit, crop or stretch: what is the difference?
When you request a size with a different shape than the original, something has to give. Fit keeps the entire picture and shrinks it until it fits within the box you asked for, so one dimension may end up smaller than requested. Crop fills the whole box and trims the overflowing edges equally from the center, which is perfect for banners and thumbnails where an exact shape is required. Stretch forces the exact dimensions and distorts the content, so use it only for abstract graphics or when you specifically want that effect.
For portraits, crop is usually the right choice because it keeps the face centered. For documents and screenshots, choose fit so no text is cut off.
Why use this resizer?
- Nothing is uploaded. Resizing uses your browser's canvas, so private pictures remain on your device.
- Exact control. Pixel mode, percentage mode and presets cover every common situation.
- Live preview. See the result and an upscaling warning before you resize.
- Batch and ZIP. Process dozens of pictures at once and download them together.
- No limits. No sign-up, no watermark, no daily quota.
Popular image sizes
| Use | Size (px) | Shape |
|---|---|---|
| Instagram post, square | 1080 × 1080 | 1:1 |
| Instagram post, portrait | 1080 × 1350 | 4:5 |
| Instagram story or Reels | 1080 × 1920 | 9:16 |
| YouTube thumbnail | 1280 × 720 | 16:9 |
| Facebook cover | 820 × 312 | about 2.6:1 |
| LinkedIn banner | 1584 × 396 | 4:1 |
| X (Twitter) header | 1500 × 500 | 3:1 |
| Full HD wallpaper | 1920 × 1080 | 16:9 |
These figures are the commonly recommended values at the time of writing. Social networks update their layouts regularly, so treat them as a good starting point and verify against the platform's own help page if exact placement matters.
Resolution, dimensions and file size explained
The dimensions of an image are the number of pixels along its width and height. A 4000 by 3000 photo from a phone has twelve million pixels. Displayed on a website that is 1200 pixels wide, most of those pixels are wasted, and the file loads slowly. Resizing to 1600 by 1200 reduces the pixel count by about 84 percent while the picture still looks sharp on a normal screen.
File size usually drops in proportion to the number of pixels, but the format and quality also matter. If you need a small file for an upload form, resize first and then run the picture through the compress image tool to reach an exact number of kilobytes. If you plan to print, do the opposite: keep as many pixels as possible, because printing needs roughly 300 pixels per inch for a sharp result.
Resizing down is safe, because the software averages neighboring pixels. Resizing up is never lossless, because it must guess at the missing detail. That is why the tool warns you whenever your target is larger than the original.
Tips for better results
Always work from the original file rather than from an already resized copy, so quality is not degraded twice. Use JPG for photographs and PNG for graphics with text or transparency. When making thumbnails, choose crop so the image fills the frame, and check the preview to be sure the subject stays in view. Keep the aspect ratio lock on unless you intentionally want a different shape, and rename the final files to something descriptive before you publish them.
Frequently asked questions
How do I resize an image to an exact pixel size?
Choose the Pixels mode, type the width and height you need and press Resize images. If you type only one value, the other is calculated from the aspect ratio. When both values are given you decide what happens: fit keeps the whole picture inside the box, crop fills the box and trims the edges, and stretch forces the exact size even if the picture gets distorted.
Are my photos uploaded to a server?
No. Resizing is done by your browser on your own device, with no upload, no account and no tracking. You can disconnect from the internet after the page loads and the tool keeps working. That makes it appropriate for private photos, scans and documents.
Does resizing reduce the file size too?
Usually yes, because fewer pixels mean less data. Halving the width and height cuts the number of pixels to a quarter. If you also need to hit a specific number of kilobytes, run the result through the compress image tool, which lets you set a target such as 200 KB.
What happens if I make an image bigger?
The tool will do it, but a warning appears first. Enlarging cannot invent detail that is not in the original, so the picture becomes soft or blurry. For the best result, start from the highest resolution version you have and only shrink it.
Which size should I use for Instagram, YouTube or Facebook?
Use the presets: Instagram square 1080 by 1080, portrait 1080 by 1350, story 1080 by 1920, YouTube thumbnail 1280 by 720, Facebook cover 820 by 312, LinkedIn banner 1584 by 396 and X header 1500 by 500. Platforms change their recommendations from time to time, so check the current guidance if a result looks cropped.
Can I resize many pictures at once?
Yes. Add as many files as you like, choose one set of options and every picture is processed in a single pass. Several results are packaged into one ZIP file, and each file name gets the new size appended, for example holiday-1080x1080.jpg, so nothing gets overwritten.
Can I rotate or flip pictures at the same time?
Yes. The rotate menu turns images by 90, 180 or 270 degrees and the mirror option flips them horizontally. The preview below the options shows exactly what the first file will look like before you press the button.
Is it really free?
Yes, with no daily limit, no watermark and no sign-up. A few ads are shown on the page away from the buttons, and they do not block any feature.
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