ChatGPT Images 2.5 vs Nano Banana 2: Which One is Better?

OpenAI shipped ChatGPT Photos 2.5 on September 8, and the pitch was particular: sharper particulars, richer textures, extra pure lighting, and modifying that truly respects what you did not ask it to vary.

The corporate says image-generation latency dropped by as a lot as 50% in contrast with Photos 2.0, and two new fashions—GPT-Image-2.5 Flare and GPT-Picture-2.5 Sunburst—now sit within the API, with Flare because the quick default and Sunburst constructed for premium modifying precision.

It is the direct sequel to a comparison we ran again in Could, when GPT Picture 2 and Nano Banana 2 traded wins throughout eight classes. GPT Picture 2 took extra of them however suffered from a particular oversharpening artifact every time a immediate piled on too many constraints. That overview closed with a particular query hanging over it: would OpenAI’s subsequent mannequin repair that downside?

So we ran it again.

Similar evaluator’s eye, six classes carried over or tailored from earlier rounds, identical prompts fed to each fashions. Google’s facet of the take a look at makes use of Nano Banana 2—Google’s identify for Gemini 3.1 Flash Picture—not the slower, extra deliberate Nano Banana Professional.

It is a same-tier matchup: OpenAI’s new fast-and-precise mannequin towards Google’s fast-and-precise mannequin.

What truly modified in GPT-Picture 2.5

OpenAI’s picture fashions have a sample of transport with a signature flaw. The mannequin behind the unique GPT Picture 1 picked up a persistent heat, yellow coloration forged that the web nicknamed the “piss filter”—a tint OpenAI by no means totally defined and by no means totally mounted.

GPT Picture 2 traded that downside for a unique one: feed it a immediate with too many stacked constraints and it could oversharpen the output right into a crunchy, over-processed mess, thick with artifacts.

Neither flaw confirmed up on this spherical. Each picture we generated with Photos 2.5 held its coloration stability and its element at full complexity, with out the yellow forged or the crunchy over-sharpening that marked its two predecessors. That is an actual, seen repair, and it exhibits most clearly within the steampunk and portrait checks—each are essentially the most photographically coherent ChatGPT outputs we have examined throughout three mannequin generations.

OpenAI additionally added product options that do not present up in a side-by-side picture take a look at however matter for workflow: Sketch, which helps you to draw a tough format instantly in ChatGPT as a technology reference, immediate sharing, inline feedback on particular picture areas, and format templates for posters and merch. On the API facet, high quality tiers now run from low up by way of a brand new excessive and max, above the place Photos 2.0 topped out.

Right here is how OpenAI’s new mannequin stacks up towards Google’s finest provide.

Lettering density: the Kellerman’s {Hardware} scene

That is the punishing one—a gritty 2 a.m. intersection the place practically each floor carries readable textual content: a ghost signal, spray-painted graffiti, vinyl storefront lettering, a torn live performance poster, a stenciled curb, and a sticker-covered payphone.

Nano Banana 2 rendered nearly every part cleanly. The one slip is a payphone sticker that duplicates its personal textual content in a garbled manner—a minor, easy-to-miss flaw.

ChatGPT Photos 2.5 added a element Nano Banana skipped completely: a lamppost with overlapping stapled flyers, torn and weathered, precisely because the immediate described.

However the mannequin’s personal street-art tag reads like “STILLL HERE” with an additional L, and the apostrophe in “KELLERMAN’S” on the ghost signal is lacking or unreadable. For a mannequin whose complete pitch is precision textual content rendering, two separate legibility slips in a single picture is an actual miss.

Aesthetically talking, OpenAI’s mannequin generated a extra practical scene, however when it comes to textual content it didn’t pay the identical quantity of care. Even when the picture appears higher, the textual content technology wasn’t nearly as good as Google’s.

Winner: Nano Banana 2.

Spatial consciousness: The steampunk clock tower

A demanding aerial composition take a look at: a five-plane depth scene with an enormous clocktower whose faces want to indicate completely different instances in legible Roman numerals, plus six different textual content parts scattered from foreground to background.

ChatGPT Photos 2.5 produced the extra atmospheric picture by a transparent margin—seen steam rising off rooftops, a river chopping by way of the mid-ground, richer tonal vary throughout the 5 depth planes. The letters are additionally simpler to learn on this technology.

Nano Banana 2’s environment is flatter, however its two seen clock faces each render legible Roman numerals—XII, III, VI, IX—at related hand positions which was not what the immediate requested for.

Winner: GPT Photos 2.5, on the power of following directions higher with out sacrificing realism.

Illustration: The anime spirit medium

This immediate asks for a Studio Ufotable-style key visible: a woman mid-transformation into religious power at a torii gate, with a nine-tailed kitsune fox and a Makoto Shinkai-painted twilight sky.

ChatGPT Photos 2.5 delivers the very best sky of any take a look at we have run on this complete sequence—an precise solar disc, water reflection, and mountain silhouette that genuinely earns the Shinkai comparability. The uneven eyes land effectively too. The place it drifts from the immediate is the “dissolving into power” instruction, which the mannequin reinterprets as an electric-crackle impact operating by way of her hair fairly than the flowing, translucent dissolve described.

Nano Banana 2’s wispy blue-white power path is the nearer literal match to that particular line. Neither mannequin rendered a convincing nine-tailed fox.

Winner: ChatGPT Photos 2.5, on total visible influence, even with the interpretive drift.

Realism: The rooftop architect

A cinematic portrait with an extended checklist of impartial constraints: beige trench coat, spherical glasses, blueprints held within the left hand particularly, golden-hour lighting, shallow depth of subject, movie grain.

ChatGPT Photos 2.5 produced beautiful gentle—the solar disc is seen instantly behind her, and the pores and skin micro-texture is superb. The pores and skin is just too clean, however the total surroundings may be very practical, like taken with an analog digicam.

Curiously sufficient, including some instructions that might ordinarily make the picture unhealthy high quality truly find yourself rising its realism. Here’s a technology after including key phrases like “practical, highlights, crushed shadows, uneven flash, blown out pores and skin tones, candid second, shot on a telephone digicam.”

Nano Banana 2 retains the fuller composition, with right-hand placement as a substitute of left-handed, and provides a legible blueprint label—”PROJECT: 124 DUANE ST”—that the majority renders skip completely.

Winner: Nano Banana 2, for one shot, GPT for repeated iterations.

Agentic analysis: The Bitcoin timeline

Each platforms can analysis a subject earlier than rendering it, so we requested for a widescreen Bitcoin historical past timeline in kids-drawing model, with a strict bar on factual accuracy. That is the class that mattered most for the comparability, and it is the place the most important hole confirmed up.

ChatGPT Photos 2.5 constructed a clear two-row infographic with particular dates all through—and certainly one of them is fallacious. It labels 2023 because the 12 months Bitcoin ETFs have been accepted within the U.S. The SEC truly accepted the primary spot Bitcoin ETFs on January 10, 2024—a full 12 months later, though the futures ETFs have been truly accepted that 12 months, so it might be an interpretation concern.

Nano Banana 2’s output is much less structured however portrays related occasions, which says one thing about how little variance the mannequin exhibits on repeated prompts. That stated, it hedges the ETF approval and the fourth halving right into a “2023–2024” bracket as a substitute of asserting a single fallacious 12 months, so nothing it states is technically false.

Winner: Nano Banana 2. A confidently fallacious date issues extra in a class particularly testing whether or not “agentic reasoning” produces correct output.

Summary ideas: A immediate product of invented phrases

This one used a immediate constructed nearly completely from phrases that do not imply something: “A lady consuming shmfiyxl in Lyxin. Subsequent to her, her Lymglsushing performs Lakishkark.” There isn’t any dictionary definition for the dish, the venue, the companion, or the sport—every mannequin has to invent one after which resolve how one can present its work.

ChatGPT Photos 2.5 solved it by writing the nonsense straight into the scene as textual content. “Lyxin” glows on a neon signal above a smooth, futuristic restaurant. “Lakishkark” is printed on the field of a board sport the girl’s alien tablemate is taking part in. The made-up phrases cease being summary the second they develop into signage you may truly learn.

Nano Banana 2 took the alternative strategy. It constructed a heat, culturally particular scene—a Guatemalan market stall, a girl in a standard huipil, an orc-like creature taking part in a hybrid stringed-and-pipe instrument—and browse “performs” as taking part in music fairly than taking part in a sport, a unique however equally legitimate interpretation. Nothing within the body ties again to “Lyxin” or “Lakishkark” particularly, although; the invented phrases by no means floor as seen textual content wherever.

Winner: ChatGPT Photos 2.5. Turning undefined ideas into legible labels is a extra literal reply to a immediate that offers it nothing else to work with.

The decision

Nano Banana 2 gained three of six classes on this spherical, so it’s mainly a tie. It’ll all rely in your expectations and the best way you work together with the mannequin. ChatGPT Photos 2.5 additionally mounted the oversharpening downside that dogged its predecessor, and its illustration output this spherical is arguably essentially the most visually hanging single picture both mannequin has produced throughout two full rounds of testing.

What separates the 2 is not total high quality however very tiny particular issues: checkable misses, a spelling error in a lettering-heavy scene, a fallacious 12 months in a research-driven infographic, and so on.

However when it comes to total aesthetics and high quality they’re just about on par.