ThumbGenViral YouTube thumbnails, made by AI on your PC.
Generate scenes, cut out characters, erase and rewrite text, and polish everything in a Photoshop-style editor. 100% local: no account, no cloud, no per-image fees.
Made with ThumbGen
Real thumbnails made with ThumbGen. Click any one to see it full size.
Everything a thumbnail needs, in one app
Two modes: Create for fast AI generation, and Edit, a Photoshop-style editor with AI tools built in.
AI backgrounds
Describe a scene and get several variations in seconds, with style presets for gaming, reactions, tech, finance and more.
Reference images
Copy the composition, colour palette or layout of any thumbnail you like.
Subject cut-out
Click a person or character to cut it out, with the classic white outline, glow and shadow.
Photoshop-style editor
Layers, masks, blend modes, brushes, selections, magic wand, transform, crop, curves and full history.
Magic eraser
Brush over text, logos or objects and they vanish. The background fills in naturally.
Edit text in any image
Finds text baked into a picture, erases it and gives you an editable layer in the same style.
Background remover
One click for photos or cartoon/game characters, then swap in a colour, a gradient, an image or an AI scene.
Character generator
Describe a character in photo, 3D-cartoon, anime or blocky-avatar style. It arrives already cut out.
AI repaint
Change expressions, outfits and objects with a prompt: shocked face, red hoodie, gold crown.
4× AI upscale
Sharpen small or blurry pictures before they go into your thumbnail.
Export anything
JPG kept under YouTube's 2 MB limit, PNG, WebP or layered PSD, in several sizes at once.
Private & offline
Everything runs on your computer. Your images never leave your PC.
Pro version coming soon
ThumbGen is invite-only while we grow. The beta is free for everyone right now, and beta users get early access to Pro when it launches.
- Free public beta: every feature on this page
- Invites roll out to creators first
- Pro: coming soon
Runs on almost any modern PC
No graphics card needed: the beta runs the AI on your processor. A faster CPU and more RAM just make it quicker.
Minimum
| System | Windows 10 or 11, 64-bit |
| Processor | Any 64-bit CPU from the last ~8 years |
| Memory | 8 GB RAM |
| Disk space | ~3.5 GB (SD-Turbo model + AI editing tools) |
| Internet | Only for the first model download |
Recommended
| Processor | 6+ cores (about 30 s per image) |
| Memory | 16 GB+ RAM (needed for SDXL-Turbo and quality repaint) |
| Disk space | ~12 GB with every optional model |
| Screen | 1920×1080 or larger |
Up and running in three steps
ThumbGen is a single file: no installer, no account.
Download
Get ThumbGen.exe with the button above and run it.
Allow it to run
If Windows shows "Windows protected your PC", click More info → Run anyway. This beta isn't code-signed yet.
Pick your models
Choose the AI models on first launch. They download once, and after that ThumbGen works fully offline.
Questions
Is ThumbGen really free?
Yes. The public beta is free with every feature. ThumbGen is invite-only while it grows, and a Pro version is coming later. Beta users will get early access.
Why does Windows warn me when I open it?
New programs without a paid code-signing certificate trigger Microsoft SmartScreen. Click More info, then Run anyway. You only have to do this once.
Do my images get uploaded anywhere?
No. Every AI model runs on your own computer. The internet is only used to download the models the first time, and to fetch a YouTube thumbnail if you paste a link.
Where are the AI models stored? How do I uninstall?
Models and settings live in %LOCALAPPDATA%\ThumbGen. To uninstall, delete ThumbGen.exe and that folder. To keep everything next to the exe instead, put an empty portable.txt beside it.
Does it need a graphics card?
No. The beta runs on the CPU, so it works on almost any PC. GPU acceleration is planned.
Can I use the thumbnails on a monetised channel?
The images you make are yours, but the AI models have their own licences. SD-Turbo and SDXL-Turbo use Stability AI's community licence, which limits commercial use for larger businesses. Check it before using AI-generated backgrounds commercially.
Mac or Linux?
Windows only for now.
Make your next thumbnail in minutes
Free public beta for Windows. No account needed.