Change the expression. Keep the face.
Your thumbnail's expression sets the video's energy before anyone reads the title. FatThumb's emotion mode swaps a calm look for shock, excitement, or skepticism — while your identity stays locked exactly as it was.
How it works
Three steps from zero to upload-ready.
Open a thumbnail in the Modify editor
Pick any thumbnail you have generated in FatThumb — fresh from a batch or pulled back out of version history — and open it in the Modify editor.
Switch to emotion mode and describe the expression
Type the expression you want in plain words: shocked with wide eyes, confident smirk, mid-laugh, deadpan. There is no fixed preset list — if you can describe it, you can request it.
Generate and compare against the original
The new expression arrives as a fresh variant. Compare it side by side with the original, star the winner, and keep both in version history in case you change your mind.
Features
Everything you need for the click.
Changes the expression, nothing else
Emotion mode instructs the model to change only the facial expression. The background, composition, lighting, and every other element of the thumbnail stay as they were.
Still recognizably you
Face shape, features, and proportions are locked to the original image during the edit. The emotion changes; the person does not.
Described in words, not picked from a menu
Skip the six-preset dropdown. Describe exactly what you want — a skeptical raised eyebrow, exaggerated horror, a barely-contained grin — and the model renders that specific expression.
Test which emotion earns the click
Generate expression variants of the same thumbnail and compare them side by side. Shock versus curiosity versus confidence is a measurable choice, not a guess.
One photo session, every emotion
Upload 1–5 photos to your Person profile once. After that, every expression is a sentence you type, not a session you book — no re-lighting, no re-shooting, no performing reactions on camera.
Every variant saved
Expression edits land in your version history alongside the originals. Star the keepers, revert any time, and never lose the calm version while chasing the shocked one.
FAQ
Questions & answers
How does FatThumb keep my identity intact when changing the expression?
Emotion mode sends the model a scoped instruction: change only the facial expression described, keep the subject's face shape, features, and proportions locked exactly as in the original image, and change nothing else. The expression is the variable; the identity is the constant.
Which expressions can I create?
Any expression you can describe in words. Instead of a fixed list of presets, you type the expression you want — shocked, excited, angry, curious, smug, exhausted, or something more specific like a doubtful side-glance. The model renders your description.
Can I change the expression on a photo I upload?
The expression changer works on thumbnails generated in FatThumb. To start from your own look, create a Person profile with 1–5 photos of your face, generate a thumbnail with it, then change the expression on any result. Your likeness carries through the whole chain.
Will an expression edit change the background or other elements?
No. Emotion mode is scoped to the facial expression only. For other changes, the Modify editor has dedicated modes: modify for general edits, text, style, and face for face-region changes.
How is emotion mode different from face mode?
Emotion mode changes only the expression on the existing face. Face mode handles face-region changes — like applying a different Person — and includes a strictLikeness toggle that keeps the face exactly as-is, with no beautifying, aging, or restyling.
Does each expression change cost credits?
Yes — each edit is a generation and uses credits at your plan's per-thumbnail rate. Viewing, comparing, starring, or downloading variants from version history costs nothing extra.
Shoot the face once. Prompt every emotion after that.
Generate your first 5 thumbnails free — no card, no designer, your face consistent from the first run.