Resize Image Online — Free Image Resizer

Resize Image

Resize images to the exact width and height you need, in pixels, without uploading anything to a server. Lock the aspect ratio to avoid distortion, or set fully custom dimensions for thumbnails, avatars, banners, and product shots.

Processed in your browser. This tool runs entirely on your device. Your image is never uploaded to us.

Drag & drop images here

or browse files · JPG, PNG, WEBP up to 20 MB

Your live preview will appear here

Overview

Resizing in the browser means there's no waiting on uploads or downloads and no privacy trade-off — your photo is decoded, redrawn at the target resolution with high-quality smoothing, and exported on the spot. It's the fastest way to hit a platform's required dimensions or simply make a giant photo a manageable size.

What this tool does

The resizer redraws your image at a new pixel width and height using high-quality interpolation. You can keep the original proportions with an aspect-ratio lock so the second dimension fills in automatically, or unlock it to stretch to any exact size, then export to JPG, PNG, or WEBP.

Problems it solves

A platform requires an exact image size (e.g., a 1080×1080 social post or a 400×400 avatar).
A photo is too large in dimensions and slows down a page or won't fit an email.
You need consistent thumbnail sizes across a gallery or catalog.
An upload form rejects images above a certain resolution.

Key benefits

Set exact pixel dimensions for width and height
Lock aspect ratio to prevent stretching
High-quality smoothing keeps results sharp
Instant preview before you download

Who it's for

Social media managers hitting platform size specsWeb developers generating thumbnails and responsive assetsSellers preparing marketplace product photosAnyone shrinking a large camera photo for sharing

How to use it

1
Upload your image
Drop a JPG, PNG, or WEBP into the upload area. The tool reads its current width and height and pre-fills them for you.
2
Enter your target dimensions
Type the width and/or height in pixels. With the aspect-ratio lock enabled, the other value updates automatically to avoid distortion.
3
Pick an output format
Choose JPG, PNG, or WEBP for the resized result depending on whether you need transparency or the smallest possible file.
4
Resize and download
Click Resize to render the new image, review the before/after preview, then download your perfectly sized file.

Example input and output

A landscape illustration of two buildings against a gradient sky, shown at its original 1600 pixel width. — Original — 1600px wide

The same landscape illustration resized to 800 pixels wide, with identical framing and proportions. — Resized — 800px wide, same framing

Example input

A 1600 × 1000 screenshot exported as WEBP at quality 85 — 44.8 KB.

Example output

The same image resized to 800 × 500 and exported at the same quality 85 — 14.2 KB.

Halving the width cut the file by 68% without touching the quality setting, because the discarded pixels were never being displayed. These are measured figures — resizing first is almost always a bigger win than compressing harder.

How wide should the image be?

Bar chart comparing recommended image export widths: 2400px for full-bleed heroes, 1920px for standard heroes, 1200px for article images, 800px beside text, 600px for thumbnails and 400px for avatars. — Export at the width the image is actually displayed at. Anything beyond it is bytes a visitor downloads and never sees.

Image dimensions by platform

Sizes each platform is built around. Matching them avoids the crop or the upscale a platform would otherwise apply for you.

Recommended pixel dimensions and aspect ratios for common web and social placements
Placement	Dimensions	Ratio
Open Graph / link preview card	1200 × 630	1.91:1
Instagram square post	1080 × 1080	1:1
Instagram portrait post	1080 × 1350	4:5
Instagram story / Reel	1080 × 1920	9:16
YouTube thumbnail	1280 × 720	16:9
LinkedIn shared image	1200 × 627	1.91:1
X (Twitter) in-stream image	1600 × 900	16:9
Website hero, full-bleed	2400 × 1260	1.91:1
Blog / article inline image	1200 × 675	16:9
Product photo (ecommerce)	2000 × 2000	1:1
Grid or card thumbnail	600 × 400	3:2
Avatar / profile picture	400 × 400	1:1

Open Graph is the strictest of these — most platforms crop or reject anything that is not close to 1200 × 630.

Common use cases

Meet social media specs

Resize to exact dimensions for Instagram posts, YouTube thumbnails, LinkedIn banners, or Twitter/X headers in seconds.

Build website thumbnails

Generate consistent thumbnail and card sizes so your grids and galleries line up cleanly and load fast.

Shrink photos for email

Bring oversized camera photos down to a sensible resolution so they send and open without issues.

Prepare marketplace listings

Match the required product image dimensions for Etsy, eBay, Amazon, or Shopify without cropping out detail.

Tips & best practices

Keep the aspect ratio locked
Unless you deliberately want to stretch an image, leave the aspect-ratio lock on so your photo keeps its natural proportions and never looks squashed.
Don't upscale beyond the original
Enlarging an image past its native resolution can't add detail and may look soft. Start from the highest-resolution source you have when you need a larger size.
Resize first, then compress
Reducing the pixel dimensions already cuts file size dramatically. Follow up with the compressor if you need to hit a specific kilobyte target for the web.

Resize Image — frequently asked questions

Yes, and it is on by default. Enter a width and the height follows automatically, so nothing stretches or squashes. You can unlock the ratio to set both dimensions independently, but doing so distorts the image — if you need a different shape, crop to it first and then resize.

Making an image smaller does not reduce quality at the new size — it discards pixels that were never being displayed. High-quality smoothing keeps the result crisp. Enlarging is the problem: upscaling cannot invent detail, so a stretched image looks softer while the file gets bigger. If an image is too small, you need a better source.

Yes — 20 MB per file, and up to 20 files at a time. Canvas dimensions are also capped at 8192 pixels on either side, which prevents a very large image from exhausting your browser's memory. Those limits cover essentially every photo a phone or camera produces.

Yes — that is how this tool works by default. The image is read from your device, resized on a canvas in the page, and re-encoded locally. No network request carries the file. Open your browser's developer tools and watch the Network tab while you resize if you want to confirm it.

Resizing changes how many pixels the whole image has, keeping everything in frame. Cropping cuts away part of the frame, keeping the remaining pixels at their original scale. If the aspect ratio is wrong for where the image is going, crop first to fix the shape, then resize to set the final dimensions.

WEBP for anything going on the web — it is smaller than both alternatives and keeps transparency. PNG when the file has to open in older desktop software or a print workflow and needs to stay lossless. JPG for photographs that must work absolutely everywhere, including email templates where WEBP support is unreliable.

You can queue up to 20 files, though the resizer works through them one at a time so you get a precise preview of each. That matters more than it sounds: the right dimensions usually differ per image, and a single batch width applied blindly tends to produce something wrong for half the set.

1080 x 1350 for an Instagram feed post, 1080 x 1080 for a square, and 1080 x 1920 for stories and Reels. Link previews need exactly 1200 x 630 — most platforms crop or reject other ratios. YouTube thumbnails are 1280 x 720. The full reference table on this page covers the rest.

Only if you want it to. You pick the output format when you resize, so you can change dimensions and format in one step, or keep the original format and change dimensions alone. Resizing and converting in a single pass avoids a second re-encode, which matters for lossy formats.

Sources and further reading

The claims on this page about formats, browser behaviour, and performance come from these primary sources rather than from us.

Responsive imagesMDN Web Docs
How srcset and sizes let a phone download a smaller file than a desktop.
Optimize Largest Contentful Paintweb.dev
Why an oversized hero image is usually the thing holding back a page's LCP score.
Cumulative Layout Shift (CLS)web.dev
Why images need declared dimensions to avoid shifting the page as they load.
Google Images best practicesGoogle Search Central
What Google asks for from images it indexes, including alt text and filenames.