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Preview of Ultrawider — 21:9 Video Fill

Ultrawider — 21:9 Video Fill by Ultrawider

Stretch 16:9 videos to fit any 21:9, 32:9, or other ultrawide monitor. Smart WebGL warp keeps faces round. Free on YouTStretch 16:9 videos to fit any 21:9, 32:9, or other ultrawideube.

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About this extension
You bought an ultrawide monitor. Almost every video on the web is still 16:9 — sitting in the middle of your screen with thick black bars eating ~26% of your real estate.

Ultrawider fixes that. It stretches any 16:9 video to fill your 21:9, 32:9, or any other ultrawide monitor — without distorting the faces in the center.

HOW IT WORKS

Most "stretch to fit" tools do uniform scaling: people get fat, everyone looks like they're in a fun-house mirror. Ultrawider uses a quintic non-linear warp (NLS) shader: the center 60% of the frame stays geometrically correct, and only the outer 20% on each side gets stretched to fill the extra width. Faces stay round. Sports replays look natural. Movie close-ups stay cinematic.

When pixel access isn't available (cross-origin embedded players or sites that block pixel reads for content protection), Ultrawider automatically falls back to Crop mode — a uniform CSS scale that fills the screen the same way "object-fit: cover" does, sacrificing top/bottom edges instead of pillarboxing.

The result: your ultrawide monitor finally pays for itself.

FEATURES

• Smoothie mode — quintic NLS WebGL2 shader. The math that keeps faces round while edges stretch. Tunable concavity slider so you can dial it from "subtle" to "strong" per site.

• Crop mode — CSS-only fallback that works on every video. No pixel reads required, so it works even in cross-origin embedded players.

• Auto-detect — picks the best available mode the moment you enter fullscreen. Per-host preferences remembered.

• Aspect-aware — detects your monitor's actual aspect ratio (21:9, 32:9, 21:10, 32:10, dual-stacked — anything you've got) and computes the right stretch for your geometry. No setup, no manual configuration.

• Universal video detection — works on YouTube and any other site with an HTML5 video player or embedded iframe player. No site-by-site whitelist; new video sites work automatically without extension updates.

• Zero distortion when off — toggle Off and the video returns to its original aspect, no residual artifacts.

PRICING

• Free — Smoothie + Crop on YouTube, forever. No signup, no key.

• Pro — unlocks every other video site for about $3/month (exact price at checkout).

• One-time payments via Telegram Stars (paid by card). No auto-renewal. Renew when you want, don't when you don't.

• One Pro key activates on up to 3 devices simultaneously. The least-recently-used device unbinds when you go over.

• 30-day goodwill refunds — email us and we'll process within 24 hours.

PRIVACY

• We collect: anonymous install ID, anonymous usage events (active mode, hostname-only). Usage telemetry is off by default — enable it in the popup if you want to help; anonymous error reports are always sent (hostname-only, no URLs) to keep the extension working.

• We do NOT collect: page URLs (only hostname), page content, video content, your identity, your watch history.

• License keys are passed via URL fragment (#key=...) not query parameters — so they never appear in server logs, Referer headers, or browser sync.

• Full policy at https://ultrawider.net/privacy

COMPATIBILITY

• Chrome / Edge / Brave / Vivaldi (Chromium 119+)

• Every ultrawide aspect ratio: 21:9 (3440×1440), 32:9 (5120×1440), 21:10, 32:10, portrait-stacked configurations — works on any ultrawide.

• Works in browser fullscreen, presentation fullscreen, and detected automatically when a player goes fullscreen.

FAQ

Will faces look distorted?
Smoothie's whole purpose is to keep the center undistorted. The central 60% of the frame is geometrically identical to the source; only the outer 20% on each side gets stretched. Movie close-ups, news anchors, sports broadcasters all look natural.

Does it work in browser fullscreen (F11)?
Yes — Ultrawider detects both Fullscreen API requests (the player's fullscreen button) and document-level fullscreen.

Why is Smoothie unavailable on this site?
Either the video is embedded in a cross-origin iframe Ultrawider can't read pixels from, or the site protects its content by blocking pixel access. Crop works either way and is always available — click it instead.

Can I use it on more than 3 devices?
The 3-device cap auto-rotates: the least-recently-used device unbinds when you activate on a 4th. Need a higher cap? Email hello@ultrawider.net.

Is my watch history collected?
No. We never log URLs or page content — only the bare hostname (e.g. "youtube.com") is ever sent, and usage telemetry is off by default; it only runs if you opt in from the popup.

Get your ultrawide monitor working the way you expected when you bought it.
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Permissions and data

Required permissions:

  • Access your data for all websites

Optional permissions:

  • Access your data for all websites

Data collection:

  • The developer says this extension doesn't require data collection.

Optional data collection, according to the developer:

  • Authentication information
  • Technical and interaction data
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Version
1.0.1
Size
119.31 KB
Last updated
5 days ago (Jul 5, 2026)
Related Categories
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License
All Rights Reserved
Version History
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Tags
  • dailymotion
  • social media
  • streaming
  • twitch
  • youtube
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