How We Ranked the Cheapest AI Image Generators
I ranked these models by the minimum cost of generating one image through GPT Proto, but price alone was not enough to decide what each model is good for. Three rules kept the comparison useful.
First, a model had to be currently callable through GPT Proto. A cheap model that appears in a catalog but cannot complete a request is not a recommendation.
Second, the output configuration had to be visible. A low-quality 1024×1024 draft is not directly equivalent to a 2K or 4K image. The table therefore lists both the starting price and the corresponding output tier.
Third, I separated request cost from usable-image cost:
Request cost = price of one generation request
Effective cost per usable image
= total generation, retry, editing, and upscaling spend
÷ number of images you can actually publish
This is a price-first comparison, not a same-prompt quality test. Where I recommend a model for a particular workload, that recommendation is based on its published inputs, output options, and billing structure—not an invented success rate.
6 Cheapest AI Image Generators at a Glance
| Rank |
Model |
Starting cost |
Output at this price |
100 images |
1,000 images |
10,000 images |
Best for |
| 1 |
GPT Image 1 Mini |
≈ $0.0035* |
Low-quality 1024×1024 |
≈ $0.35 |
≈ $3.50 |
≈ $35.00 |
Drafts and prompt testing |
| 2 |
Nano Banana 2 Lite |
$0.0202 |
1K |
$2.02 |
$20.20 |
$202.00 |
Predictable startup workloads |
| 3 |
Kling Image O1 |
$0.0224 |
1K |
$2.24 |
$22.40 |
$224.00 |
Reference-guided images |
| 4 |
Seedream 4.0 |
$0.0255 |
2K |
$2.55 |
$25.50 |
$255.00 |
Low-cost 2K production |
| 5 |
Seedream 5.0 Lite |
$0.0298 |
2K |
$2.98 |
$29.80 |
$298.00 |
A newer low-cost Seedream route |
| 6 |
Nano Banana 2 |
$0.0402 |
1K |
$4.02 |
$40.20 |
$402.00 |
A broader production workflow |
*GPT Image 1 Mini is token-based. OpenAI lists a low-quality 1024×1024 image at $0.005, while GPT Proto lists image-output tokens at 30% below the direct rate. The approximately $0.0035 figure is therefore a starting estimate for that configuration, not a fixed price for every image. Prompt input, higher quality, and larger dimensions add cost. The batch totals above assume one request per retained image, with no retries, editing, or upscaling.
1. GPT Image 1 Mini: Cheapest for Drafts and Prompt Testing
GPT Image 1 Mini is the cheapest starting point in this list. OpenAI describes it as a cost-efficient version of GPT Image 1 that accepts text and image inputs. It offers low, medium, and high quality at 1024×1024, 1024×1536, and 1536×1024. On OpenAI’s published rate card, a low-quality square image costs $0.005; GPT Proto lists the underlying image-output rate at $5.60 per million tokens instead of $8.00. That puts the equivalent starting output cost at roughly $0.0035, before the comparatively small prompt-input charge.

The appeal is straightforward. A team can use it to reject weak prompts, compare compositions, produce placeholder art, or create many early variations without spending production-model prices on every attempt.
The catch is equally important: GPT Image 1 Mini does not have one universal per-image price. A high-quality portrait or landscape costs more than a low-quality square draft. Its lighter positioning also means it should not be treated as a drop-in replacement for a premium image model when small text, surface detail, or final photorealism matters.
My verdict: choose GPT Image 1 Mini when iteration volume matters more than maximum final-image detail. It is the cheapest starting option, but not automatically the cheapest finished image.
2. Nano Banana 2 Lite: Cheapest Predictable Flat-Rate Option
Nano Banana 2 Lite costs $0.0202 per 1K generation on GPT Proto. It accepts either text or an image as input, so the same route can support new images and image-guided changes. Unlike GPT Image 1 Mini, its entry price is not tied to a quality selector or a variable number of output tokens.

That predictability is valuable for a startup. At the published rate, 1,000 requests cost $20.20 and 10,000 cost $202 before retries. A product team can attach that number to a feature limit or customer plan without first estimating how many output tokens each request might consume.
The trade-off is resolution. Nano Banana 2 Lite is a 1K route; it does not offer the 2K and 4K output choices listed for the full Nano Banana 2 model. If every generated image must later be enlarged, the $0.0202 headline price stops telling the whole story.
My verdict: GPT Image 1 Mini starts lower, but Nano Banana 2 Lite is the cleanest answer when “cheapest” means a stable, easy-to-forecast unit cost.
3. Kling Image O1: Cheapest for Reference-Guided Images
Kling Image O1 costs $0.0224 for a 1K image—only $0.0022 more than Nano Banana 2 Lite. It supports both text and image input, and Kling’s documentation allows up to 10 reference images for tasks involving a subject, scene, style, or other visual constraints.

That makes it more interesting than its third-place price ranking suggests. A product that needs characters, objects, or visual direction carried from supplied images may get more value from a reference-oriented route than from the absolute cheapest text-to-image request.
There is still a boundary. The listed output tier is 1K, and this article does not have a controlled same-prompt test proving that Kling produces more usable results than the two cheaper options. The recommendation is conditional: choose it because you need its reference workflow, not because a price table proves better image quality.
My verdict: paying an extra $2.20 per 1,000 images over Nano Banana 2 Lite is reasonable when reference images are central to the job. For plain text-to-image drafts, the cheaper options remain easier to justify.
4. Seedream 4.0: Cheapest 2K Image Generator
Seedream 4.0 costs $0.0255 per 2K image on GPT Proto. That is the first major specification change in the ranking: Nano Banana 2 Lite and Kling Image O1 are listed at 1K, while Seedream 4.0 reaches 2K for roughly two and a half cents.

For 1,000 images, its base generation bill is $25.50. That is only $5.30 more than Nano Banana 2 Lite’s 1K bill. If a workflow would otherwise enlarge every 1K result, Seedream 4.0 deserves a direct cost comparison rather than being dismissed because it sits fourth in the table.
Why not call it the best low-cost image model? Age. Seedream 4.0 is an older generation, and Seedream 5.0 Lite costs only $0.0043 more per image. Teams that care about using the newer route may decide that a $4.30 difference per 1,000 images is too small to justify staying on 4.0.
My verdict: Seedream 4.0 has a narrow but legitimate role—the cheapest fixed-price 2K output in this six-model shortlist. Pick it for unit economics, not because it is the newest Seedream option.
5. Seedream 5.0 Lite: Newer 2K Output for Under Three Cents
Seedream 5.0 Lite costs $0.0298 per 2K image. It supports both text and image input and points to the Seedream 5.0 Lite release; it should not be confused with the more expensive Seedream 5.0 Pro.

Its strongest price argument appears when it is placed beside Seedream 4.0. The difference is $0.0043 per image, $0.43 per 100 images, or $4.30 per 1,000. For a small production run, that gap is modest enough that many teams should evaluate the newer model before choosing the older one solely to save money.
At 10,000 requests, however, the difference grows to $43. A high-volume service with simple prompts may still prefer Seedream 4.0 if its own tests show no meaningful improvement in usable-output rate. That last condition matters: model generation cost should follow your results, not a version number.
My verdict: Seedream 5.0 Lite is the more sensible default for teams that want low-cost 2K generation without deliberately selecting a previous generation. Seedream 4.0 remains the strict price winner.
6. Nano Banana 2: Best All-Round Choice Below Five Cents
Nano Banana 2 starts at $0.0402 for a 1K image on GPT Proto and also offers 2K and 4K output tiers. Google’s model documentation highlights image generation and editing, broader aspect-ratio support, multilingual text rendering, and optional grounding with web and image search.

It is the most expensive entry in this cheap-model list. At 1K, 1,000 requests cost $40.20—almost twice the $20.20 bill for Nano Banana 2 Lite. Teams producing disposable previews should not pay that difference merely because the non-Lite version has more features.
The calculation changes when a single model must cover draft generation, edits, multiple output sizes, and images containing text. A route that reduces model switching or manual repair can be cheaper at the workflow level even when its first request costs more. This article does not claim a measured reduction in retries, but the wider output range gives teams more room to test that possibility with their own prompts.
My verdict: choose Nano Banana 2 when saving two cents matters less than having 1K, 2K, and 4K options in the same model family. It is the broadest production candidate here, not the lowest-cost request.
The Cheapest Request May Not Produce the Cheapest Usable Image
A price table can tell you what a request costs. It cannot tell you how many requests will survive review.
Imagine that Model A costs $0.0202 but needs three attempts to produce one acceptable image. Its generation cost per usable result becomes $0.0606. Model B costs $0.0402 and succeeds on the first attempt, so its cost remains $0.0402. These are hypothetical retry counts, not measured claims about Nano Banana 2 Lite or Nano Banana 2, but the arithmetic shows why a one-cent difference can disappear quickly.
Four costs commonly sit outside the advertised number:
Retries: anatomy errors, unwanted text, weak composition, or inconsistent products can force another generation.
Editing: replacing a background, correcting a label, or restoring a product detail may require another request.
Upscaling: a cheap 1K result is less cheap if every accepted image must be enlarged.
Human review: someone still has to check spelling, prices, logos, product geometry, and brand compliance.
The most useful number for a startup is therefore not cost per API call. It is cost per approved image. Record total spend and the number of images that passed review for each model over a representative batch. Even a test of 50 to 100 prompts will tell you more about your own economics than a generic quality ranking.
What About Free AI Image Generators?
Free browser tools win when the job is occasional and manual. ChatGPT Free includes image creation with separate tool limits. Google Gemini offers image access whose limits can change with the model, request complexity, and system capacity. Bing Image Creator is another practical option for casual browser generation.
They are not included in the six-model ranking because $0 access and a production API solve different problems. A startup may need automated requests, stable unit costs, usage logs, rate planning, and the ability to switch models. A free web interface does not necessarily provide those conditions.
If you only need a few personal images, start free. If you need a browser-focused comparison, see our guide to the best free AI image generators. Move to pay-as-you-go generation when manual limits become the bottleneck.
Which Cheap AI Image Generator Should You Choose?
There is no useful single winner without a workload attached. My shortlist is:
| Your priority |
Pick |
Why |
Main trade-off |
| Lowest possible draft cost |
GPT Image 1 Mini |
Starts around $0.0035 for a low-quality square image |
Variable token and quality cost |
| Predictable 1K pricing |
Nano Banana 2 Lite |
Fixed $0.0202 starting price |
No 2K or 4K tier |
| Reference-guided generation |
Kling Image O1 |
Supports text, image input, and multiple references |
1K output |
| Cheapest fixed-price 2K output |
Seedream 4.0 |
$0.0255 per 2K image |
Older model generation |
| Newer low-cost 2K route |
Seedream 5.0 Lite |
Only $0.0043 more than Seedream 4.0 |
Higher bill at large volume |
| Wider production workflow |
Nano Banana 2 |
1K, 2K, and 4K options with generation and editing |
Highest starting price in this list |
For a startup prototype, I would begin with GPT Image 1 Mini for rough exploration and Nano Banana 2 Lite for a feature that needs predictable billing. Before launch, run the same representative prompt set through two or three models and calculate cost per approved image. Do not subscribe to six separate tools before you know which two actually fit the product.
How to Access Cheap AI Image Models With One API Key
GPT Proto lets you fund one account and access multiple image-model routes. You can compare the available options in the AI image generator or review the platform’s pricing before setting a test budget.
The simplest setup does not require you to understand every API field first:
Open the model page you want to use.
Click Try this model.
Select Copy as and copy the model setup.
Paste it into your preferred coding agent or AI assistant.
Tell the assistant which language, framework, or app you are using. It can then explain the remaining integration steps and adapt the request for your project.

Keep the API key in an environment variable rather than pasting the secret itself into a public prompt. The copied model information and request structure are enough for the assistant to guide the setup.
If you prefer to start directly from the API example, copy the cURL request displayed on the model page. The following example uses the Seedream 5.0 Pro route shown in GPT Proto:
curl --request POST "https://gptproto.com/api/v3/doubao/dola-seedream-5-0-pro-260628/text-to-image" \
--header "Authorization: Bearer $GPTPROTO_API_KEY" \
--header "Content-Type: application/json" \
--data '{
"prompt": "A tiny origami fox sailing a teacup across a moonlit puddle",
"size": "2048x2048",
"enable_base64_output": false,
"enable_sync_mode": false
}'
With enable_sync_mode set to false, use the Check Status example on the same model page to retrieve the result after submission. For one of the six cheaper models ranked above, open its own page and copy its endpoint and request fields. Model switching is not always a one-word change: GPT Image, Kling, Seedream, and Gemini routes can use different paths and parameters.
Final Verdict
Use a free web generator if you only need a handful of personal images. Use GPT Image 1 Mini when the goal is to produce drafts and test prompts at the lowest possible starting price. Choose Nano Banana 2 Lite when a startup needs a predictable unit cost.
For higher-resolution work, Seedream 4.0 is the strict 2K price winner, while Seedream 5.0 Lite offers the newer route for a small premium. Nano Banana 2 costs the most in this shortlist, but its wider output range makes it the better candidate when one model must cover more of the production workflow.
The final decision should come from your approval rate, not the first number in a pricing table. Compare these models in the GPT Proto AI image generator, run a representative batch, and calculate what each usable image actually costs.