Why did the whole room change?

Interior imagery in the training data is full of coordinated redesigns. Without a capitalised scope word and an explicit preservation list, the model follows the genre rather than the instruction.

Does capitalising ONLY actually help?

It strengthens the scope signal, and in this category the default pull is strong enough to need it. Both this and the billboard prompt use the device.

Why does the new furniture look like it is floating?

Missing contact shadows. Ask for them explicitly — it is the fastest fix for the most obvious tell in an interior edit.

Can I change a window or a floor?

Not well. Those define the room's light, so preserving the lighting while changing them is contradictory. Structural changes want a fresh generation, not an edit.

GPT Image 2.5 prompt — replace furniture without redecorating the room

ONLY, in capitals. The word is doing real work.

The same kitchen with the white chairs replaced by wooden ones, lighting and angle unchanged

The original photograph of a kitchen with white chairs

InputResult

Settings the Swap one piece of furniture in a real room photo prompt ran at
Mode	Model	Quality	Size	Ratio	Credits
Image to Image	Think	Standard	1K	3:2	10 cr

Published by OpenAI as an example for this model — not generated on this site. Model: gpt-image-2.5-sunburst. Source: OpenAI The published example ran at 1536x1024, a legal size we do not currently offer; the frame here is the same shape at our nearest size.

White chairs become wooden chairs in a photographed kitchen, and nothing else moves. Interior visualisation is a large commercial use for image editing and it fails in one particular way — you ask for a chair and get a redesigned room. The fix is a capitalised ONLY plus an explicit list of the photographic properties that must survive.

In full

The prompt, nothing cut

In this room photo, replace ONLY the white chairs with chairs made of wood.
Preserve camera angle, room lighting, floor shadows, and surrounding objects.
Keep all other aspects of the image unchanged.
Photorealistic contact shadows and fabric texture.

251 characters

Run it here

This exact prompt, at these exact settings

The mode and all five settings are locked to this template, so there is nothing to line up by hand. Press Run this prompt above and the panel opens filled in — prompt, mode, quality, size and frame — and your first image needs no account. If your plan sits below what this ran at, the line under the panel says so.

This example was published at Think · Standard · 1K. A free run is Fast · Standard · 1K, so expect less fine detail and softer small text. The composition is the same; the finish is not.

3 levers

What is safe to change

Most libraries publish this list and stop, which is why so many copied prompts come back worse than the original: the swappable nouns are the safe half. The three sections under it are the other half — the clauses that are doing the work, the ones that break it if you touch them, and why it is written in this order.

The capitalised ONLY
Scope, emphasised. Interior imagery is full of coordinated redesigns, so the pull toward "restyle the room" is strong and a lowercase "only" is a weaker signal than it looks.
The photographic property list
Camera angle, room lighting, floor shadows, surrounding objects. These are properties of the photograph rather than of the chairs, and they are what drift when the frame is regenerated.
The contact-shadow clause
"Photorealistic contact shadows" is the detail that decides whether the new furniture is standing on the floor or floating above it. It is the first thing an eye notices and the last thing people think to ask for.

Three ways to break it

Each one is a real failure with a reason attached. A rule without a reason is not usable.

01Not naming the object by a distinguishing feature
"The white chairs" works because colour separates them from everything else in frame. "The chairs" in a room with two sets is ambiguous, and the model will pick.
02Leaving out contact shadows
Without them the replacement sits in the room without touching it. This is the single most reliable tell of an interior edit and it is one clause to prevent.
03Swapping something structural
A chair is an object in the room. A window, a wall or a floor is the room, and changing one means regenerating the light — at which point the preservation list you wrote is asking for something incompatible.

Why it is written this way

Inside the Swap one piece of furniture in a real room photo prompt

Interior visualisation is one of the largest genuinely commercial uses of image editing — furniture retail, property staging, renovation quotes — and it has one dominant failure mode. You ask to change a chair and you get a beautifully redecorated room in which the chair has also changed.

The reason is in the training data. Interior imagery clusters around before-and-after transformations and styled catalogue shoots, where changes are coordinated: new chairs come with a new rug, new light and a new palette, because that is what a designer would do. A model asked to change chairs in a room is sitting inside that distribution, and a mild instruction does not get it out.

Hence ONLY in capitals. Emphasis in a prompt is not magic, but capitalisation of a scope word measurably strengthens it, and this is a case where the default pull is strong enough to need it. The official prompt uses the same device for the same reason the billboard prompt capitalises EXACT.

The second half is a list of things that are not the chairs: camera angle, room lighting, floor shadows, surrounding objects. Every one is a property of the *photograph* rather than of the furniture, and that is exactly why they need naming. When the frame is regenerated, the photograph itself is up for renegotiation — the viewpoint can shift slightly, the light can warm, the shadows can lengthen. None of that is what you asked for, and none of it is prevented unless stated.

The last line is the craft one. "Photorealistic contact shadows and fabric texture" — contact shadows being the small dark contacts where an object meets the floor. They are the difference between furniture standing in a room and furniture floating in front of it, and they are the first thing that reads as wrong even to someone who could not say why. One clause.

Where it stops working is structural change. A chair is an object in the room; a window is the room. Change a window and you change the light, at which point "preserve room lighting" is asking for two incompatible things and the model will pick one.

4 questions

Swap one piece of furniture in a real room photo — common questions

Why did the whole room change?: Interior imagery in the training data is full of coordinated redesigns. Without a capitalised scope word and an explicit preservation list, the model follows the genre rather than the instruction.
Does capitalising ONLY actually help?: It strengthens the scope signal, and in this category the default pull is strong enough to need it. Both this and the billboard prompt use the device.
Why does the new furniture look like it is floating?: Missing contact shadows. Ask for them explicitly — it is the fastest fix for the most obvious tell in an interior edit.
Can I change a window or a floor?: Not well. Those define the room's light, so preserving the lighting while changing them is contradictory. Structural changes want a fresh generation, not an edit.