Can I resize by percentage instead of exact pixels?

Yes. Switch to Percent mode and drag the slider (1–200%) or click a preset like 50% or 150%; the tool computes the target dimensions from the original size and shows them. Pixel mode lets you type precise width and height values instead.

What do the fit modes do when the aspect ratio is unlocked?

When you unlock the chain and set non-matching dimensions, the fit mode decides how the image maps into the target box. Stretch fills it (distorting), Contain letterboxes the whole image inside the box, and Cover fills the box and crops the overflow — ideal for social thumbnails.

Does keeping the aspect ratio prevent distortion?

Yes. With the lock enabled, changing the width updates the height (and vice versa) proportionally, so the image never stretches. Unlocking lets you set arbitrary dimensions, at which point the fit mode controls the result.

What presets are included?

Display presets like Full HD (1920×1080), HD, and 4K; web presets like Thumbnail (300×300), OG image (1200×630), and Favicon (512×512); and social presets including Instagram square, Instagram portrait, Story/Reel (1080×1920), and Twitter header.

Can I change the file format while resizing?

Yes — keep the original format or convert to JPEG, WebP, or PNG. A quality slider controls compression for the lossy formats (it is disabled for PNG since PNG is lossless).

Is the image uploaded to resize it?

No. Resizing is done locally with the canvas API and the result reports the new dimensions and the before/after size. Your image never leaves your browser, so private images stay private.

Image Resizer

Resize images to exact pixels or by percentage in your browser — lock the aspect ratio, choose a fit mode, apply social/display presets, convert format, and download. Nothing is uploaded.

About this ToolHow it works, benefits & use cases

Resize an image to exact pixels or by percentage, with a live preview and no upload. Drop a file (PNG, JPG, WebP, GIF up to 25MB) and Image Resizer reads its dimensions, then lets you type a target width and height in pixels or drag a percentage slider with handy 25–200% presets. A lock toggle keeps the aspect ratio so you scale proportionally without distortion; unlock it to hit arbitrary dimensions and pick a fit mode — Stretch, Contain (letterbox), or Cover (crop). A set of presets covers common display and social sizes (Full HD, 4K, OG image 1200×630, Instagram square, Story/Reel, Twitter header, and more). You can convert the output format (keep original, JPEG, WebP, or PNG) and set a quality level for lossy formats. The preview re-renders as you tweak, and the result reports new dimensions, before/after size, and the size change before you download. Everything runs in your browser.

How to Use

1Drop or pick an image to resize — it loads at its original dimensions.
2Choose Pixels or Percent mode: type a width/height (px) or drag the percentage slider / pick a preset.
3Keep the chain locked to preserve the aspect ratio, or unlock it and choose a fit mode (Stretch, Contain, or Cover).
4Optionally apply a display/social preset (e.g. 1200×630 OG image, 1080×1080 Instagram).
5Set the output format and quality, review the live preview and the size change, then click Download.

Key Benefits

Resize by exact pixels or by percentage with quick presets
Aspect-ratio lock for distortion-free scaling
Fit modes when unlocked: Stretch, Contain (letterbox), or Cover (crop)
Built-in display and social presets (Full HD, 4K, OG, Instagram, and more)
Convert format (JPEG, WebP, PNG) with an adjustable quality slider
Live preview plus before/after size and dimension stats
Runs entirely in your browser — nothing is uploaded

Common Use Cases

Resizing a photo to an exact width for a blog or product page
Generating a 1200×630 Open Graph image or a social-sized thumbnail
Scaling a screenshot down by percentage to fit a layout
Producing a 512×512 favicon source or app icon from a larger image
Cropping to fill a fixed box with Cover fit for consistent thumbnails

Upload an image to resize

Click to upload or drag and drop

Accepted: image/* • Max 25 MB

PNG, JPG, WebP, GIF — max 25MB. Everything stays on your device.

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