Pro Thumbnail Preview for YouTube

Professional thumbnail testing tool for YouTube.

Ready to stop wasting views and start growing your channel? See exactly how your thumbnail and title will perform — before you upload! Tired of guessing if your thumbnail stands out in search results or on the homepage? Pro Thumbnail Preview lets you instantly replace any YouTube video's thumbnail and title with your own custom ones, right on the live page. Test how it looks next to competitors, on mobile sizes, blurred (to mimic the first 1-2 seconds viewers scan) or checks contrast (Light vs Dark). Boost your Click-Through Rate (CTR) with real-world previews — no uploads needed, everything stays local on your device. Free Version Features: Edit Mode: Swap in your local thumbnail + custom title on YouTube Home, Search, or Channel pages (Latest/Popular/Oldest videos). Mobile Size Test: Preview how it looks at small sizes (160x90 px). Full Version (One-Time Payment – Lifetime Access): Blur Test — Checks FOCUS and HIERARCHY. The 1.8-Second Rule, use a blur effect on thumbnail to see which elements truly catch the eye. Focus test thumbs with blur. Contrast Test — Checks CONTRAST (Light vs Dark). The human eye first registers shapes and contrast (light/dark), and only then color. If a thumbnail looks good in black and white, it will look great in color. Packaging Rating — Get a quick score on how strong your thumbnail + title combo is. Title Manager (creating sections to store title) — An Idea Vault for your best title ideas. Save title in Edit mode (save to your computer). Loading Saved Titles inside Edit Mode and Rate Packaging Privacy-First Design We never see your thumbnails, titles or data — all processing happens locally on your computer. Ready to stop guessing and start growing your channel? Install now — free to start! Questions? Reach out: prothumbnailpreview@gmail.com