Most website images are published at whatever size the camera or the designer exported — often 4000 pixels wide for a slot that displays at 800. The visitor pays for that waste with slow pages. This free tool carries the sizes websites actually use as one-click presets: 1920×1080 hero banners, 1200×630 Open Graph cards, 1200×800 blog featured images and the classic content sizes. Upload, pick the slot the image is destined for, and download a file that fits it exactly.
Everything runs in your browser — private, watermark-free and unlimited — and the WebP export option can cut image weight by a further quarter to a third compared with JPG at the same quality.
Match the file to the slot, not the camera
The rule of web images is simple: a file should be as close as possible to the size at which it will be displayed. A hero banner that spans the screen wants 1920×1080 — big enough for full-HD monitors, pointless beyond that for a standard banner. A blog’s featured image typically displays between 800 and 1200 pixels wide, so the 1200×800 (3:2) preset covers retina screens without bloat. In-article photos sit in a 700–900 px column: 1024×768 or 800×600 is plenty. And the 1200×630 Open Graph size is what Facebook, LinkedIn, WhatsApp and Slack pull when your page is shared — skip it and the share preview is a random crop of whatever image the scraper finds first.
Why this is an SEO task, not just housekeeping
Google measures your pages with real-user data, and the Largest Contentful Paint (LCP) — usually the hero or featured image — is a core ranking signal. An oversized hero is the most common self-inflicted LCP wound: a 1.5 MB photograph where a 250 KB resize would look identical. Resizing to display size, then exporting WebP at 80–90% quality, routinely takes 70–85% off image weight. Faster pages rank better, convert better and cost less to host. Do it at upload time, every time, and the discipline compounds across your whole media library.
Fill, fit and the responsive picture
Fill centre-crops to the slot’s ratio — right for heroes and featured images, where a full-bleed look matters and the centre of the photo carries the story. Fit preserves diagrams, screenshots and product shots whole, padding with your brand colour. Modern sites also serve several sizes of one image through srcset, letting phones download small files and desktops large ones: export the same master at 1920, 1200 and 800 wide with this tool and you have a responsive set in under a minute. Whichever modes you use, keep the original file archived — you can always resize down from a master, never back up.
Favicons and the small end of the scale
At the opposite extreme sit icons: browsers and phones ask for square files from 16 px up to 512 px (the PWA icon size). Our dedicated 512×512 resizer is preset for exactly that world. Between the hero and the favicon, the presets on this page cover the working sizes of a normal site — no Photoshop licence, no upload queue, no guessing.
Galleries, shops and email: the supporting sizes
Beyond the headline slots, three more sizes earn their keep. Product and gallery grids almost always render square or 4:3 thumbnails, so a consistent 800×800 or 1024×768 export set keeps a shop looking curated instead of chaotic. Email newsletters display images at 600–700 px wide in most clients; export at 1200 wide (double, for retina) and the same file serves the campaign and the blog version of the story. Author avatars and team photos are square jobs — 800×800 from this tool, or the round version from our circle crop tool. Cover these five roles — hero, social card, featured, content, square — and a website’s entire image system is under control.
Related tools
Facebook Post Resizer (1200×630) · Resize Image to 512×512 · Versión en español: Redimensionar para Sitio Web · Online Image Resizer Tool.
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