Nano Banana Prompt Formula: A 60-Second Guide

Nano Banana (Google's Gemini 2.5 Flash Image) is incredible at natural-language photo editing and keeping a face consistent across edits — but keyword-soup prompts like "portrait, cinematic, 8k, masterpiece" still produce mush.

Why it matters

Nano Banana isn't tuned for keyword lists. It's tuned for description. The official rule is "describe the scene, don't just list keywords" — a clear sentence beats a pile of tags every time.

The other half most people miss: for edits, the model needs to know what to change AND what to keep. Leave that out and it quietly redraws your whole image.

The 6-part formula

Every reliable Nano Banana prompt fits this shape:

• Verb — the operation, up front: Create, Restore, Replace, Transform.
• Subject — who or what, specifically.
• Action / context — what they're doing and where.
• Composition — framing and camera language (85mm lens, low angle, wide shot).
• Style & lighting — mood, film stock, light direction.
• Constraints — for edits, exactly what to keep the same (the secret sauce).

3 ready-to-run prompts

1. Natural-language photo edit — swap one object (keep the ratio)

Verb: Using the provided image, replace
Subject: the [old object] with [new object]
Context: keep it in the same position and perspective
Composition: match the original camera angle and framing
Style & lighting: match the original lighting direction, shadows, color temperature, and material realism
Constraints: keep everything else in the image exactly the same — background, other objects, and the original aspect ratio

Why it works: it names the single change and then locks everything else with an explicit "keep exactly the same" line. That one sentence is what stops Nano Banana from regenerating the entire scene.

3 tweaks:

• For removals, add: "fill the gap naturally with matching texture, grain, and focus."
• Add "preserve realistic shadows and reflections" for glossy surfaces.
• If edges look off, add "blend the new object's edges seamlessly into the scene."

2. Professional headshot from a selfie (4:5)

Verb: Using this photo, create
Subject: a professional headshot of the same person
Context: framed from the chest up, looking at the camera, wearing a smart-casual blazer
Composition: 85mm lens, shallow depth of field, subtle catchlight in the eyes
Style & lighting: soft, diffused studio light, clean neutral-gray background, bright and airy color grade
Constraints: preserve the exact facial identity, proportions, and natural skin texture; 4:5 portrait ratio

Why it works: the constraint line ("preserve the exact facial identity… natural skin texture") is what keeps it recognizably you instead of a generic AI face.

3 tweaks:

• Swap the background color to match a brand palette.
• "warm, approachable expression" vs "confident, serious expression."
• Change the blazer/outfit to fit the context (startup, corporate, creative).

3. Turn yourself into a 3D collectible figurine (2:3)

Verb: Using this image, turn
Subject: the person into a 3D collectible figurine
Context: standing on a round transparent acrylic base, with collectible toy packaging behind it
Composition: product-photography framing, 2:3 portrait ratio
Style & lighting: glossy vinyl toy finish, soft studio lighting with a gentle rim light
Constraints: preserve the person's facial identity, hairstyle, and outfit colors

Why it works: it pins the style (glossy vinyl, packaging) while the constraint line preserves identity, so the toy still looks like the real person.

3 tweaks:

• "Funko-Pop style, oversized head" for the blind-box look.
• Add "displayed on a designer's desk with a 3D-modeling screen in the background."
• Switch to a pastel studio backdrop for a cleaner social-ready shot.

Iteration tips

Nano Banana is conversational — treat it like a back-and-forth, not a one-shot.

• Change one variable per turn so you know what moved the result.
• Refine with "keep everything the same, but make the lighting warmer."
• Start with a strong verb; it sets the whole operation.
• Use positive phrasing ("an empty street") instead of "no cars."
• Name materials and lenses — specificity beats adjectives.
• Build a 360° character reference sheet first if you need the same character across scenes.
• For anything with readable text, logos, or infographics, switch to Nano Banana Pro.
• Generate at higher resolution (2K–4K) with Pro for print-ready output.
• Save the prompts that work as templates with [brackets] you can swap.

Quick troubleshooting

• The whole image changed when I only wanted one edit → add "keep everything else in the image exactly the same."
• The face looks plastic / over-edited → add "preserve natural skin texture, avoid over-sharpening."
• Text or a logo came out garbled → switch to Nano Banana Pro and put the exact words in quotes.

A/B test checklist

• Run the same prompt with vs without the constraint line — see how much it drifts.
• Try base Nano Banana vs Pro on anything containing text.
• Change only the lighting or lens between runs to isolate what each does.

Read the full guide & try it

Full formula breakdown, six prompt structures, and the vocabulary that gives you control: How to Write Nano Banana Prompts

40+ ready-to-run prompts grouped by use case (editing, portraits, face swap, product, logos, restoration, thumbnails, comics): Best Nano Banana Prompts

Need a tool to run them in? Best Nano Banana AI tools