Uwarp
Input image
Resized image

Upload an image and set resize options below—the preview appears here.

Resize options

Unit

Recommended for photos. Percent mode always scales uniformly.

Which dimension adjust?

New width (px)

Resize image online

Resize PNG, JPEG, and photos online in pixels or percent. Scale up or down, stretch when needed, preview output size, download PNG in your browser.

What is image resize?

Image resize changes the pixel width and height of a photo or PNG. Set absolute dimensions in pixels, scale by percent, or stretch width and height independently when proportions are unlocked. This page adjusts pixel count—not DPI metadata or physical inch sizes. Upload an image, choose options, preview output dimensions, and download PNG—all in your browser.

Common resize search intents

Upload above, set unit and dimensions, preview, then download—these queries map to the same scaling workflow.

  1. Resize PNG: Resize PNG uploads with alpha preserved—set width and height in px or scale by percent before PNG export.
  2. PNG resizer: Use a PNG resizer in the browser: read original and output pixel sizes on screen, no server upload.
  3. Change image resolution: Change image resolution by setting new pixel width and height—constrain proportions to keep aspect ratio intact.
  4. Stretch image online: Stretch image online when proportions are off in pixel mode—set width and height independently for non-uniform scale.
  5. Make photo larger: Make a photo larger up to 8192 px on the longest edge with high-quality Canvas interpolation and live preview.
  6. Image size increase: Increase image size with percent mode above 100% or target pixel dimensions—compare before and after in the preview panel.

Resize controls

Pixels, percent, stretch, and aspect ratio options.

  1. Pixels or percent: Absolute px sizing or uniform percent scale.
  2. Constrain proportions: Lock aspect ratio when resizing by one dimension.
  3. Independent stretch: Set width and height separately when proportions are off.
  4. Width or height drive: Choose which pixel dimension you set when constrained.
  5. Live preview: Output updates as you change options.
  6. PNG download: Save the result as resize-image.png.

How to change image resolution

Steps for online image scaling and stretching.

  1. Upload the image: Drop or click in the input panel (15 MB max).
  2. Pick unit and size: Use pixels for exact dimensions or percent for proportional scale.
  3. Stretch only if needed: Disable Constrain proportions in pixel mode to stretch width and height differently.
  4. Check output dimensions: Read the resulting width × height under the preview.
  5. Download PNG: Save when the preview matches your goal.

Tips for resizing

Better scaling and stretch results.

  1. Prefer downscaling: Enlarging soft images can look blurry—start from the largest source you have.
  2. Use percent for halves: 50% or 25% is faster than calculating pixel targets manually.
  3. Keep proportions on: Avoid accidental stretch on portraits and product shots.
  4. Stretch with intent: Disable proportions only when you need a deliberate width–height change.
  5. Watch the max edge: Output stops at 8192 px—reduce percent if you hit the limit.
  6. Compare previews: Check the right panel before download for sharpness and framing.

When to resize images

Typical uses for scaling photos and PNGs.

  1. PNG and JPEG exports: Hit exact pixel widths for icons, banners, or storefront assets.
  2. Smaller file size: Shrink large photos before email or upload with percent downscale.
  3. Social dimensions: Scale toward platform width and height guidelines in pixel mode.
  4. Square or custom ratios: Turn off proportions to reshape toward a square or non-uniform target.
  5. Print pixel prep: Set pixel dimensions before handing off to layout or print tools.
  6. Quick one-off scale: Resize a single file in the browser without opening desktop apps.

Why use this resize tool

Benefits of browser-based scaling.

  1. Px and percent: Match common PNG resizer and stretch workflows in one page.
  2. Private: Images stay on your device—no server upload.
  3. Dimension readout: See original and output pixel sizes on screen.
  4. Smooth scaling: High-quality Canvas interpolation for upscaling and downscaling.
  5. Optional stretch: Unlock proportions when you need non-uniform width and height.
  6. Free: Unlimited previews and downloads.

Technical details

How resize processing works here.

  1. Canvas drawImage: Source bitmap scaled to target width and height with smoothing enabled.
  2. Percent mode: Both dimensions multiplied by new value ÷ 100.
  3. Constrained pixels: Secondary dimension derived from aspect ratio of the upload.
  4. Independent pixels: Separate width and height when proportions are off—enables stretch.
  5. Alpha channel: Preserved through scale and PNG export.
  6. Input limits: 15 MB upload; 8192 px max input and output edge.

Frequently Asked Questions

Have questions? We have answers.

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