Best AI Image Generator 2026 - Ranking From My Own Tests

The best AI image generator in my 27 September 2026 ranking is Nano Banana Pro: a 9.0/10 average and a flawless "PIEKARNIA ŻÓŁĆ" shop sign, at from $0.0747 per image. The most quality per dollar comes from GPT Image 2.5 ($0.0432 per image, one flat price per image, accented letters right), and the most accurate lettering came from Nano Banana 2, the only model that scored 10/10 on the sign. Below: the full table, notes on each model, the method and cost examples.

Quick answer: which image generator for which job

• Best quality: Nano Banana Pro - 9.0/10, near the top in every one of five prompts.
• Best price for a good image: GPT Image 2.5 - at the time of writing the cheapest model that scored above 8 in my test, and the price does not rise with quality.
• Accurate text in images: Nano Banana 2 (sign 10/10, zero letter errors in my August typography test), followed by Nano Banana Pro, GPT Image 2 and 2.5 (9.5 each).
• Photorealism and portraits: Nano Banana Pro and Seedream 5.0 Pro - both 9/10 for a portrait with hands.
• 4K: Nano Banana Pro (1K, 2K, 4K) or GPT Image 2 (4K, e.g. 3840x2160 at 16:9).
• Several variants at once and banners: Nano Banana 2 - up to 4 images per request, aspect ratios up to 8:1.
• Cheapest drafts: Z-Image Turbo ($0.02 per image), with a lower score and English or Chinese text only.

AI image generator ranking 2026

The scores come from my image generator ranking and my GPT Image 2.5 test, run the same day with the same prompts (both write-ups are in Polish). I list the models available on Jantaris.

\ In the test the model appeared as Qwen-Image 3, with no variant name. \\* I ran Z-Image Turbo locally on an RTX 4090 with the same prompts.

"From" means higher resolutions cost more. GPT Image 2.5 and Sunburst have one price on Jantaris regardless of quality.

Scores per prompt

Why a Polish sign: "ŻÓŁĆ" packs four accented letters into one short word, so it is a quick stress test for lettering beyond plain English. If a model drops a dot or an acute accent, you spot it immediately.

Nano Banana Pro - best single image

Nano Banana Pro is Google's Gemini 3 Pro Image. It combines up to 14 reference images, offers 10 aspect ratios from 21:9 to 9:16 and three resolutions: 1K, 2K and 4K. Each request returns one image, and prompts can run to 32,000 characters.

It had the highest average in the ranking and no score below 8.5: 9.5 for the sign and 9 each for the market, the portrait and the pierogi. One thing to watch: Nano Banana models sometimes add text you did not ask for (example below, under Nano Banana 2), so I read every line before a client sees it.

At the time of writing 4K costs only a little more than 1K in this model, so it is my pick for print and large frames. Comparisons: Nano Banana Pro vs GPT Image 2.5 and Nano Banana 2 vs Nano Banana Pro.

Nano Banana 2 - lettering and batches

Nano Banana 2 (Gemini 3.1 Flash Image) is the faster sibling: a 1K image usually takes 10-30 seconds, one request returns up to 4 images, and there are 14 aspect ratios including extreme 8:1 and 1:8. Resolution goes from 0.5K to 4K, with up to 14 references.

It was the only model to score 10/10 on the sign, because it also added a correct "OTWARTE" (open) plate. In my August typography test (a sign, a poster and a neon with a Polish pangram) it made no letter errors, though on the poster it invented festival dates and an address on its own. Weak spot: the pierogi (7.5), folded more like gyoza.

GPT Image 2.5, Sunburst and GPT Image 2 - quality at a fair price

GPT Image 2.5 is the faster of OpenAI's two 2.5-generation models; GPT Image 2.5 Sunburst is the slower variant built for long edit chains where a character or product must not drift. Both take up to 16 references, quality from low to max and prompts up to 32,000 characters. On Jantaris you pick 1024x1024, 1536x1024, 1024x1536 or auto.

On 27 September both variants got the sign right at every quality level (9.5). Sunburst at max scored 8.8; Flare (which is gpt-image-2.5 on Jantaris) scored 8.6 at max and 8.5 at high. What surprised me: in four of five prompts both variants produced nearly the same frame, and Sunburst won on details such as hands. Note: I generated at 16:9 in the test, while GPT Image 2.5 on Jantaris has three sizes, so you would crop 16:9 from 1536x1024.

GPT Image 2 at medium quality scored 8.7 and had zero errors in my August typography test. It has 16 aspect ratios from 1:3 to 3:1 and 1K, 2K and 4K output, so on Jantaris it, not 2.5, is the way to get 4K from OpenAI. Details: GPT Image 2.5 vs Sunburst and Nano Banana 2 vs GPT Image 2.5.

Seedream 5.0 Pro - portraits and posters

ByteDance positions Seedream 5.0 Pro for posters and covers with text in the frame. It accepts up to 10 references, offers 1K, 1.5K and 2K and 8 aspect ratios, one image per request.

It scored 8.5 overall and 9/10 for the portrait: freckles, steam over the coffee and both hands correct. The sign on 27 September was right (8.5), but in the August typography test it sprinkled accents where none belong and made at least 4 errors. I always zoom in on its lettering.

Comparisons: Seedream 5.0 Pro vs Nano Banana Pro and Seedream 5.0 Pro vs GPT Image 2.5.

Grok Imagine Image 2.0 - takes the prompt literally

Grok Imagine Image 2.0 from xAI does not rewrite your prompt or add details. It accepts up to 10,000 characters, has 7 aspect ratios and returns 1-4 images per request, text only.

It scored 8.6 in the ranking, with a correct sign at 9.5. Its weak point in the test was speed: it took the longest in the main ranking (71.5 s on average, measured with another provider). At its price it is a good alternative to GPT Image 2.5 when you want several variants in one request.

FLUX.2 [pro] - multi-reference scenes, shaky accents

FLUX.2 [pro] from Black Forest Labs focuses on photorealism and building scenes from references: up to 8 images, 1K or 2K, 7 aspect ratios plus auto, prompts up to 5,000 characters.

Its photos are solid: 8.5 each for the illustration, portrait and pierogi. Accented letters are its weak point: the sign read "ZÓŁC" instead of "ŻÓŁĆ" (5/10), and in August it made at least 4 errors across three graphics. When FLUX.2 has to make a graphic with non-English text, I leave space and add the lettering in an editor.

Comparison: FLUX.2 Pro vs Nano Banana Pro.

Qwen Image 3.0 and Z-Image Turbo - the budget options

• Qwen Image 3.0 - Alibaba, long prompts (about 4,500 tokens), text legible down to 10 px according to the maker, 1K and 2K at the same price, up to 4 images per request. In the ranking Qwen-Image 3 got the sign right (9), but the portrait (5.5) and pierogi (6.5) were weak.
• Z-Image Turbo - Z-Image Turbo, the cheapest image in this lineup. Text-to-image only, 5 aspect ratios, lettering in English or Chinese according to the maker. It scored 5.7: the sign came out as "ŽÓŁČ", and the illustration that said "no text" got a magazine title. Fine for composition drafts. More: Z-Image Turbo API and Z-Image vs FLUX.2 Pro.

How I tested

I ran the test myself on 27 September 2026 through another provider's API, not Jantaris. Full write-ups (in Polish): image generator ranking and GPT Image 2.5 test.

• Five prompts: a market with an older vendor and dill, a Kraków bakery with the sign "PIEKARNIA ŻÓŁĆ", a flat illustration of a person at a laptop with a llama (no text), a portrait of a freckled 40-year-old holding coffee, and pierogi with onions and sour cream from above.
• Settings: 16:9, "1K" resolution where the model has it, a fixed seed where the model accepts one.
• One take per prompt, no cherry-picking.
• Local models (Z-Image Turbo and Qwen-Image 2.1) on my RTX 4090.
• The 0-10 scores are mine and subjective. I measured generation times with another provider, so they may differ on Jantaris.

On top of that, my typography test of 14 August: three tasks with Polish text (a sign, a poster, a neon), including GPT Image 2, Nano Banana 2, Qwen-Image 3, Seedream 5.0 Pro and FLUX.2 [pro].

What an image costs - examples

Prices fill in from the price list in USD. For models with resolution tiers it is the lowest tier:

Work out other combinations, including 2K and 4K, in the AI cost calculator. Studio shows the cost before you click Generate, and the API returns it in estimated_cost. Failed generations cost $0. The minimum top-up is $10, there is no subscription and the balance does not expire.

How I choose in practice

1. I check composition cheaply in Z-Image Turbo or GPT Image 2.5.
2. Graphics with text go to Nano Banana 2, Nano Banana Pro or GPT Image 2.5, and I read every letter zoomed in. More in AI text in images.
3. Final frames for print or campaigns get rendered in Nano Banana Pro at 2K or 4K.
4. Scenes built from product photos go to FLUX.2 [pro].

Every model runs in Jantaris Studio and through the API from one balance. A deeper look at the three main models: GPT Image 2.5 vs Nano Banana Pro vs FLUX.2, and how to write prompts: AI image prompt guide.

FAQ

What is the best AI image generator in 2026?

In my 27 September ranking Nano Banana Pro had the highest average (9.0/10), followed by GPT Image 2.5 Sunburst (8.8) and GPT Image 2 (8.7). All three are on Jantaris.

Which AI image generator renders text most accurately?

Nano Banana 2 scored 10/10 on the "PIEKARNIA ŻÓŁĆ" sign and made no letter errors in my August typography test. Nano Banana Pro, GPT Image 2 and GPT Image 2.5 were also error-free on the sign. FLUX.2 [pro] and Z-Image Turbo mangled the accents.

What is the cheapest AI image generator?

Of the models I tested, Z-Image Turbo has the lowest price ($0.02 per image), but it scored 5.7/10. Among models that scored above 8, GPT Image 2.5 ($0.0432 per image) is the cheapest at the time of writing.

Which model is best for photorealistic images?

In my test the portrait with hands earned 9/10 for Nano Banana Pro, Seedream 5.0 Pro and GPT Image 2.5 Sunburst at max quality. For product shots built from several references, FLUX.2 [pro] works well.

Do the test results apply to Jantaris?

The models are the same, but I tested them through another provider's API. Settings can differ: GPT Image 2.5 on Jantaris has three fixed sizes instead of 16:9. Make one test image before a large batch.

Can I generate AI images for free?

Jantaris has no free plan or starter credits; the minimum top-up is $10. Google and OpenAI offer limited free generation in the Gemini and ChatGPT apps, with limits they set.