How do I resize a photo to Instagram's dimensions?

Type 1080 into Width (px) with the aspect ratio locked, and the height follows the photo's shape: a 4000 × 3000 photo becomes 1080 × 810. For a 1080 × 1080 square or 1080 × 1350 portrait from a photo of a different shape, crop it first, since this tool resizes but does not crop.

What image formats are supported?

Any format your browser can display can be opened, including PNG, JPG/JPEG, WebP and GIF. The output is always PNG. There is no format or quality choice, and the downloaded file takes the original name with resized_ in front and a .png extension, so photo.jpg comes out as resized_photo.png.

Are my images uploaded to a server?

No. The image is read locally, drawn on a canvas and offered back as a download, so it never leaves your device.

Can I resize several images at once in a batch?

No, one image at a time. The file picker takes a single image, and dropping several files loads only the first. Each resize is a separate pass, which keeps memory use predictable for large photographs.

Does resizing keep the aspect ratio locked by default?

Yes. The button reads Aspect ratio locked when a file loads, so changing the width recalculates the height and the other way round. Click it to switch to Aspect ratio unlocked; setting both numbers independently then stretches the image, which is occasionally what you want and usually not.

How do I resize an image without losing quality?

Make it smaller, not larger, and resize from the original each time. Reducing an image discards pixels, which is normally invisible, while enlarging cannot invent detail, so the browser interpolates and the result looks soft. Because the output is PNG, resizing adds no compression artefacts of its own.

What is the best way to enlarge an image?

Go back to a larger original if one exists. Interpolation cannot recover detail that was never captured, so an enlarged image is always softer than a native one at that size. Upscaling here is for filling a layout, not for recovering resolution.

Is transparency preserved?

Yes. The output is PNG, which keeps an alpha channel, so transparent areas of a PNG or WebP stay transparent after resizing.

No. Resizing goes through a canvas, which produces a fresh image with no metadata at all, so camera details, timestamps and GPS location are removed. This is useful before publishing a photograph and a loss if you needed the data.

What size should I use for the web?

Match the largest size the image is displayed at, then double it only if you are serving a dedicated high-density version. Serving a 4000-pixel photograph into a 600-pixel slot is the single most common cause of a slow page.

What happens to an animated GIF?

Only the first frame is kept, because a canvas holds a single still image. Animations need a tool that understands frames.

Is there a maximum image size?

There is no limit set by the tool, but browsers cap how large a canvas can be, and phones set a lower cap than desktops. Very large panoramas are the images that hit it, and the download then fails.

Why does my resized image look soft?

Either it was enlarged, in which case softness is inherent, or it was reduced by an awkward ratio. Reducing to an exact half or quarter gives the cleanest result because whole pixels map onto whole pixels.

Why is my resized JPG bigger than the original?

Because the download is a PNG, and PNG stores photographs far less compactly than JPEG. A JPEG resized to smaller dimensions can still come out larger in bytes, especially when it is only shrunk a little. If file size matters, convert the result back to JPEG or run it through an image compressor.

Does it work offline?

Yes. After the page has loaded, resizing needs no network connection.

Should I resize or compress an image first?

Resize first. Reducing dimensions removes pixels before any quality decision is made, so compressing afterwards works on a much smaller image and the two savings compound.

Image Resize

Resize images while maintaining aspect ratio

Image Resize

Drop an image anywhere on this page

or paste ⌘VPNG, JPG, WebP, GIF or any image

What is Image Resize?

Image Resize is a free online tool that lets you resize images to any custom dimension while maintaining the original aspect ratio. Whether you need to resize photos for social media, prepare images for a website, or scale down large images for email, this tool handles it quickly and efficiently.

The tool opens PNG, JPG, WebP and any other image format your browser can display. You type the exact width and height in pixels, and the aspect ratio lock, which is on by default, keeps your images from being stretched or distorted. The download is always a PNG file, whatever format you started with.

Unlike cloud-based image editors, this tool processes images entirely in your browser. Your photos are never uploaded to any server, making it the safest option for resizing personal photos, confidential documents, or any images you want to keep private. The resized image can be downloaded instantly.

A worked example shows how to resize an image for Instagram. Load a 4000 × 3000 photo called photo.jpg. With Aspect ratio locked, type 1080 in Width (px) and Height (px) changes to 810 by itself. Click Download Resized and you get resized_photo.png at 1080 × 810 pixels, which keeps the 4:3 shape and the 1080-pixel width Instagram uses for feed images. For a 1080 × 1350 portrait or a 1080 × 1080 square, crop the photo to that shape first, because unlocking the ratio and typing both numbers stretches the picture instead of cropping it.

Resizing is done by the browser's canvas with its default smoothing, so reducing an image looks good and enlarging one does not: no tool can restore detail that was never captured, and upscaling produces a softer version of the same information. Two side effects of going through a canvas are worth knowing. Metadata does not survive, so EXIF, GPS coordinates and colour profile are dropped, which is good for privacy. And the output is re-encoded as PNG rather than copied, so a JPEG photo can come out as a larger file even at smaller dimensions.

How to use Image Resize?

Upload your image
Drag and drop an image or click to browse and select one from your device. The tool shows its file size, its current width and height, and a preview.
Set the dimensions
Enter the width or height in pixels. With Aspect ratio locked, the other field updates to match; click the button to switch to Aspect ratio unlocked if you want to set both freely.
Check the numbers
The preview shows the original image, so check the Width (px) and Height (px) fields for the size you will get before downloading.
Download the resized image
Click Download Resized to save the image. The file is a PNG named resized_ plus the original name, with the extension changed to .png.

Key Features

Starts at the Original Size
Both fields are prefilled with the image current dimensions, so you edit the number you care about instead of looking it up first
Aspect Ratio Lock
On by default: change the width and the height follows, or the other way round, so the image is never stretched by accident
Exact Pixel Dimensions
Type the exact width and height in pixels you need, larger or smaller than the original
Opens Common Formats
Reads PNG, JPG, WebP and other formats your browser supports, and saves the result as PNG

Frequently Asked Questions

Yes, Image Resize is free, no signup, and adds no watermark to your images.

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Read the full Image Resize guide

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Image Resize

What is Image Resize?

How to use Image Resize?

Upload your image

Set the dimensions

Check the numbers

Download the resized image

Key Features

Starts at the Original Size

Aspect Ratio Lock

Exact Pixel Dimensions

Opens Common Formats

Frequently Asked Questions

Related Tools

EXIF Remover & Metadata Viewer

Image Compress

Image Dither

Random Number Generator

Comments

Learn more