What an OG image is
"OG" stands for Open Graph, a protocol introduced by Facebook and now used everywhere. It defines how a page looks when its link is shared: as a preview card with image, title and description. The image on that card is the OG image — and in a feed full of links it's often the one thing that wins the click. Without it, a shared link looks bare and gets clicked less.
The dimensions: 1200 × 630
The established standard is 1200 × 630 pixels (ratio ~1.91:1). This size displays cleanly on Facebook, LinkedIn, WhatsApp and most platforms. More rules:
- Keep the important part centered — some services crop the edges slightly.
- Large, legible text — the card appears small; fine type disappears.
- JPG or PNG, ideally under 1 MB — large images get rejected or load slowly on some platforms.
The meta tag
The OG image is set via a meta tag in the page <head> — with an absolute URL (not relative):
<meta property="og:image" content="https://your-domain.com/og.jpg">
<meta property="og:title" content="Page title">
<meta property="og:description" content="Short description">
<meta property="og:url" content="https://your-domain.com/page">For Twitter/X, add the card declaration, which can reuse the same image:
<meta name="twitter:card" content="summary_large_image">
<meta name="twitter:image" content="https://your-domain.com/og.jpg">The most common mistakes
- Relative instead of absolute URL — platforms need the full
https://…address, or they can't find the image. - File too large — over the platform's size limit and the image is ignored. Shrink it first with the resize and compression tools.
- Stale cache — platforms cache the preview. After a change, each platform's debug tool (Facebook Sharing Debugger, LinkedIn Post Inspector) re-reads the card.
- No image set — the platform then grabs some page image or shows nothing.
Test before it counts
Before a big share, test with the platforms' official debug tools — they show exactly how the card will look and reveal missing or wrongly sized images. That way you catch the mistake before your audience does, not after.
One image per page
A default OG image for the whole site is the minimum. More effective is a specific image per article or product — with that page's title and motif. Many modern frameworks can even generate OG images dynamically (from a title and a template), so every page automatically gets a fitting, well-designed preview. For small sites it's enough to give your most important pages a dedicated, designed image each — the design rules match a quote graphic: large text, high contrast, a clear message.