The file stays in the browser

Choose one or more images. The page reads width, height, the byte count, and the file type on this device. The file is not uploaded to Premium Launcher, and it is not sent to the launch or social site whose spec is being checked.

A launch set is usually more than one file. Product Hunt asks for a thumbnail and for gallery images. A link preview is a different image again. Run each file through the list instead of assuming one export covers every row.

Numbers come from the platform page

Each row links to the official page it was taken from, with a checked October 2026 note. If that page does not publish a pixel size, an aspect ratio, a file-size cap, or a type list, the cell says not stated. Sizes from blogs and image generators are not used.

The Open Graph protocol requires an image URL and does not publish a pixel size. Facebook's link-share documentation does publish sizes for the image it reads from og:image. Those are separate rows, because a protocol with no size and a product doc with several sizes are not the same rule.

An X summary_large_image pixel size is not stated on the current X docs site. The old card-guide URL redirects to the docs home, and the docs sitemap does not list a replacement. X does publish post and DM upload limits. Those limits are labeled as uploads, not as the card.

When the official pages disagree

Product Hunt's Help Center says a GIF thumbnail must be under 3MB. The launch guide, in the thumbnail section, says all images, GIF or not, need to be under 3MB. A PNG over that line is outside the guide. The Help Center does not state a file-size cap for that PNG.

LinkedIn's sharing-module page sets a minimum of 1200×627 and says an image less than 401 pixels wide displays as a thumbnail. The Page post preview page says the width must be more than 200 pixels, and that a width under 200 displays as a thumbnail. The photo-upload page is a third spec: at least 552×276, a recommended width of 1080, and an aspect range from 3:1 to 4:5.

Facebook's link-share images page says 1200×630 and a ratio close to 1.91:1. The sharing best-practices page says at least 1080 pixels wide for high-resolution display, and it recommends 1:1 for image link ad creatives. Bluesky's posts guide says 1,000,000 bytes in the prose and 2,000,000 bytes in the code sample. Mastodon's English posting guide, updated July 8, 2026, does not match the Japanese translation, updated January 31, 2025.

Where a page writes MB and does not define it, the result compares the file with 1,000,000 bytes and with 1,048,576 bytes per MB. It does not pick a unit the page did not name.

What a matching row does not promise

A file can meet a published minimum and still be cropped in a feed. Facebook says to stay close to 1.91:1 and does not publish a numeric tolerance, so this page shows the measured ratio and does not invent a pass band. 1200÷630 is about 1.905, which is not 1.91.

Pinterest's image Pin page states file types and a 20 MB web maximum. It does not state a pixel size. The standard image ad page recommends 2:3 or 1000×1500. Safe-zone padding on the Pin page has no canvas size, so it is not turned into a width and a height.

Aura++, EarlyHunt, IndieHunt, MakerHunt, SideHunt, and Uno Directory are not in the table. Their public submit pages did not include image pixel rules in the HTML returned for this check, and the forms render in the browser. A rule that appears only after sign-in is not guessed. Tagline length is on the launch copy character counter. A week of submissions is on the launch week planner. Directory fees are on the bulk launch cost calculator, and return math is on the launch ROI calculator. The platform list, pricing, and the other free tools are separate from these image rules.