How to resize an image
- Drop one or more images into the box, or click to browse.
- Pick a preset such as Instagram portrait or YouTube thumbnail, or type a width and height in pixels.
- Choose how to fit: stretch, fit inside with padding in a color you pick, or fill and crop from the center.
- Select the output format and quality, check the preview, then click Resize & download.
What you can do with Image Resizer
- Social media presets
- One-click sizes for Instagram square, portrait and story, YouTube thumbnail, X header and post, Facebook cover, LinkedIn banner, Open Graph, Full HD and 4K.
- Pixels or percent
- Type exact dimensions with the aspect ratio locked, or switch to percent mode and scale anywhere from 5% to 300%.
- Three fit modes
- Stretch to an exact size, fit inside with colored padding bars, or fill and crop from the center so nothing is distorted.
- Batch resize to ZIP
- Every image in the list gets the same target size, and the files download together as a ZIP named with their new dimensions.
- Smooth downscaling
- Large reductions are done in halving steps with high-quality smoothing, which avoids the jagged, shimmering look of a single big resize.
Recommended image sizes and fit modes
Every platform crops or recompresses images that don't match its expected size, so resizing first gives you control over the result. Common targets are 1080 × 1080 for an Instagram square post, 1080 × 1350 for a portrait post, 1080 × 1920 for stories, Reels and TikTok, 1280 × 720 for a YouTube thumbnail, 1500 × 500 for an X header and 1200 × 630 for link previews (Open Graph). Uploading at exactly these sizes means the platform doesn't have to rescale your picture, which keeps text and edges sharper.
When the target shape differs from your photo, the fit mode decides what happens. Fill & crop scales the image until it covers the frame and trims the overflow evenly from the edges, which suits photos. Fit inside keeps the whole picture and adds bars, useful for product shots or screenshots you can't crop. Stretch forces the exact size and distorts the image, so use it only when proportions already match. Shrinking images is safe; enlarging beyond the original resolution adds pixels but can't add real detail, so expect softness above about 150%.
Frequently asked questions
Are my photos uploaded when I resize them?
No. Resizing is done on a canvas inside your browser and the new files are generated on your device. Your images never leave your computer or phone, which makes the tool fine for personal photos, ID scans or unreleased product images.
How do I resize an image without stretching it?
Keep Lock aspect ratio ticked and enter only a width or a height; the other value follows automatically. If you need an exact size with a different shape, untick the lock and choose Fill & crop to trim the edges, or Fit inside to add padding bars instead of distorting the picture.
What size should a YouTube thumbnail or Instagram post be?
A YouTube thumbnail is 1280 × 720 pixels (16:9). Instagram uses 1080 × 1080 for square posts, 1080 × 1350 for portrait posts and 1080 × 1920 for stories and Reels. All of these are available as one-click presets in the resizer, along with X, Facebook, LinkedIn and Open Graph sizes.
Can I resize several images at once?
Yes. Drop as many images as you need. Each row shows its original and new dimensions, the preview shows the first image, and the button changes to download all resized files as one ZIP. In percent mode or with the aspect ratio locked, each image keeps its own proportions.
Does resizing reduce the file size?
Usually, yes. Fewer pixels means less data, and halving the width and height cuts the pixel count by 75%. You can also choose JPG or WebP and lower the quality slider. For the smallest files with a before/after check, run the result through the Image Compressor.