AI image models · compared
GPT Image 2.5 vs Nano Banana 2.1
GPT Image 2.5 and Nano Banana 2.1 are both AI image models that run on one varg API key. This page puts what the varg catalog states about each side by side: the price, how it is billed, what it takes and the typical time. It ranks neither on quality.
- GPT Image 2.5
- From $0.01 per run from $0.01/image
- Nano Banana 2.1
- From $0.05 per run from $0.05/image
Every model is billed at its provider's price with no markup, from one credit balance: 1 credit is $0.01.
GPT Image 2.5 vs Nano Banana 2.1: side by side
Every row is read from the varg catalog and each model's input schema. A "from" price is the cheapest request the catalog states for that model, at its own cheapest settings. For the exact price of a request, send its body to POST https://api.varg.ai/v2/estimate.
| Fact | GPT Image 2.5 | Nano Banana 2.1 |
|---|---|---|
| Made by | OpenAI | |
| Takes and makes | Text to image, Image to image | Text to image, Image to image |
| Price | From $0.01 per run | From $0.05 per run |
| Rates on the cheapest route | Quality low: $0.01/image; Quality medium: $0.02/image; Quality high: $0.06/image; Quality xhigh: $0.10/image; Quality max: $0.22/image; Other: $0.06/image | Resolution 1K: $0.05/image; Resolution 2K: $0.07/image; Resolution 4K: $0.15/image; Other: $0.15/image; Minimum charge: $0.05 |
| Billed | per image | per image |
| Typical time | ~30 s | ~20 s |
| Routes | 4 on fal | 2 on fal |
| Model id | gpt_image_2_5 | nano_banana_2_1 |
Which to pick
Each line is a difference between two rows of the table. None of it says which model's output looks better: that depends on the prompt.
Pick GPT Image 2.5 when
- you want the lower starting price: from $0.01 per run, against from $0.05 per run, each at the model's own cheapest settings.
- you want the lower starting rate: from $0.01/image, against from $0.05/image; the table gives each model's rate by setting.
Pick Nano Banana 2.1 when
- you want the shorter typical wait: ~20 s, against ~30 s, by the catalog's estimates.
Call GPT Image 2.5 and Nano Banana 2.1
One endpoint and one API key for both: POST https://api.varg.ai/v2/tools/image/call with Authorization: Bearer $VARG_API_KEY. It answers 202 with a job right away; poll GET /v2/jobs/{id} until its status is completed.
GPT Image 2.5
curl -X POST https://api.varg.ai/v2/tools/image/call \
-H "Authorization: Bearer $VARG_API_KEY" \
-H "Content-Type: application/json" \
-d '{
"model": "gpt_image_2_5",
"prompt": "A photorealistic product photo of a coffee bag labeled \"Summit Roast\" with mountain artwork, on a rustic wooden table"
}'vargai call_tool --tool image '{"model":"gpt_image_2_5","prompt":"A photorealistic product photo of a coffee bag labeled \"Summit Roast\" with mountain artwork, on a rustic wooden table"}'Nano Banana 2.1
curl -X POST https://api.varg.ai/v2/tools/image/call \
-H "Authorization: Bearer $VARG_API_KEY" \
-H "Content-Type: application/json" \
-d '{
"model": "nano_banana_2_1",
"prompt": "An infographic poster explaining how a coffee bean becomes espresso, five labelled steps, clean flat illustration.",
"aspect_ratio": "3:4"
}'vargai call_tool --tool image '{"model":"nano_banana_2_1","prompt":"An infographic poster explaining how a coffee bean becomes espresso, five labelled steps, clean flat illustration.","aspect_ratio":"3:4"}'How billing works
Every model is billed at its provider's price with no markup, from one credit balance: 1 credit is $0.01. varg's fee is on the top-up, not on the run: 5.5% of the credits you buy ($0.80 at the least), or 8% for a team workspace. Pricing
GPT Image 2.5 vs Nano Banana 2.1: questions
- Which is cheaper, GPT Image 2.5 or Nano Banana 2.1?
- GPT Image 2.5 starts lower: from $0.01 per run, against from $0.05 per run for Nano Banana 2.1. By starting rate, GPT Image 2.5 is lower: GPT Image 2.5 from $0.01/image, Nano Banana 2.1 from $0.05/image. Those are each model's cheapest settings, and the price of a request depends on what it asks for: the table lists each model's rates. For the exact price of a request before you run it, send the same body to POST https://api.varg.ai/v2/estimate.
- Can I use GPT Image 2.5 and Nano Banana 2.1 with one API key?
- Yes. Both run on varg behind POST https://api.varg.ai/v2/tools/image/call with one API key and one credit balance: send "model": "gpt_image_2_5" or "model": "nano_banana_2_1". Every model is billed at its provider's price with no markup, from one credit balance: 1 credit is $0.01.