CaptionSnap for Chrome

Same simulator, in your toolbar. Paste ad copy, see exactly where each platform clips it, hand off to the full simulator with one click. The popup is free, fully offline, and stays out of the way — no host permissions, no content scripts, no tracking SDK.

Pro features — bulk paste of 10 headlines, PNG export, ad-free browsing — live on the website. The popup's “Open full simulator” button hands your current copy off to captionsnap.io with one click.

Coming soon to the Chrome Web Store.The build is ready and the popup is feature-complete — we're finalizing icons and screenshots for the listing.

What it does

• Pick a platform (Meta, TikTok, LinkedIn, X, YouTube, Pinterest, Reddit, Snapchat) and a placement.
• Paste primary text, headline, and description.
• See live counters and a truncated preview showing exactly where the platform clamps your copy.
• One-click handoff to the full captionsnap.io simulator with your copy already loaded — for safe-zone overlays, embed snippets, and share links.

What it doesn't do

• No host permissions. The extension cannot read any page you visit.
• No content scripts. It does not inject UI into Meta / TikTok / LinkedIn ad managers — those surfaces are CSP-locked and break weekly. The popup gives you 80% of the value with none of the breakage.
• No telemetry.We don't ship an analytics SDK in the extension. Outbound links carry a UTM tag so attribution lands in our website analytics, not a tracker bundled in the popup.

Source

The extension reads the same lib/platform-specs.ts, lib/truncate.ts, and lib/share.ts as the website. When we re-verify a placement and update a spec, the next extension build picks it up automatically. See how the data stays current.