What does this post-preview tool actually show?

It renders your caption and an optional image inside a mockup of each platform’s own post card, including the real point where that platform hides the rest of the caption behind a "more" control.

Are the truncation cutoffs official numbers from each platform?

No — no platform publishes this figure, so every cutoff here is a third-party measurement, dated and sourced on the page, and can shift with app version, screen width and device.

Does the tool upload or store my caption or image?

No, everything renders in your browser from the text and image URL you provide; nothing is uploaded, saved, or sent to a server.

Which platforms does the preview support?

Facebook, Instagram, LinkedIn, TikTok, X and YouTube, each with its own measured truncation behavior; switch between them with the tabs above the preview.

Why does X show my whole caption with no cutoff?

X does not truncate a post in the timeline the way the other platforms do — its composer simply refuses text past the character limit, so whatever fits is shown in full.

Is there a version of this tool for just one platform?

Yes, the platform-specific pages below use the exact same widget defaulted to that platform, with questions and examples framed for that platform’s search intent.

Free tool

Social media post preview

Paste a caption and an image URL to see how the post will actually render in each platform’s own feed, including the exact point where that platform cuts the caption off behind a "…more" or "See more" control. This general version lets you switch between Facebook, Instagram, LinkedIn, TikTok, X and YouTube on the same caption; the platform-flavored pages below default to one platform and answer that platform’s own questions about truncation.

Platform

Your caption

Image URL (optional)

Feed posts show roughly the first 125 characters before "… more". Reels captions truncate far earlier, around 55-60 characters on the Reels tab — this tool models the main feed, not Reels, so a Reels caption will read as cut off sooner than shown here.

Instagram preview

Your accountInstagram · just now

No image URL entered

We just shipped a big update to how bulk imports work. Here's a quick look at what changed and why it makes scheduling a mont … more

Truncated after 125 characters — 60 more characters are hidden behind "… more".

How to use the social media post preview

Paste your caption. Type or paste your draft caption into the box; nothing you type is uploaded anywhere.
Add an image URL (optional). Paste a public image URL to see it in the mockup frame, or leave it blank to preview the caption alone.
Pick a platform tab. Switch between Facebook, Instagram, LinkedIn, TikTok, X and YouTube to see the same caption rendered for each one.
Read the truncation point. The preview greys out the part of the caption that falls past that platform’s real "more" cutoff.
Rewrite around the cutoff. If your hook or call to action falls in the greyed-out part, move it earlier so it survives the cutoff on every platform you post to.

Worked examples

Instagram cuts off far earlier than Facebook desktop

Instagram shows roughly 125 characters before "… more", while Facebook on desktop shows roughly 477 — the same 300-character caption reads as complete on desktop Facebook but cut off on Instagram, which the platform tabs make visible side by side.

X never truncates

X does not show a "more" control in the timeline at all — whatever fits under the composer’s character limit is shown in full, unlike the other five platforms here.