HiAPI Tools · Free AI Image Models

Free AI Image Generator: Try Low-Cost Models

Generate with FLUX.2 [klein] 4B, FLUX.1 [schnell], Z-Image or Seedream 5.0 Flash and see which fits your project. The same models cost from $0.00143 per image through the API.

Create a production API key

Account required; API calls are usage-based.

How to Compare AI Image Models

Three steps to find the best model for your image project.

01
Write a prompt

Describe the image in English or Chinese, or pick an example.
02
Pick a model and ratio

Choose FLUX.2 [klein] 4B for the lowest cost, FLUX.1 [schnell] for speed, Z-Image for photoreal looks or Seedream 5.0 Flash for Chinese prompts.
03
Compare and continue

Switch models with the same prompt, download the watermarked result, or open the winner in its playground for full quality.

The Models at a Glance

List prices through the HiAPI API, per image. Check each model page for live pricing.

Model	API price	Note
FLUX.2 [klein] 4B	$0.00143 / image	The cheapest option here, with the widest ratio range and 0.25-4 MP output tiers in the API.
FLUX.1 [schnell]	$0.005 / image	The fastest. Great for drafts, thumbnails and high-volume pipelines.
Z-Image	$0.008 / image	Strong photoreal results and five aspect ratios from square to 9:16.
Seedream 5.0 Flash	$0.025 / image	Follows Chinese prompts well and handles text in images better than most budget models.
Free preview	5 images a day, watermarked	Enough to compare. Failed generations don't count.
Full quality	playground or API	Same prompt, no watermark, full resolution, billed per image.
One API	POST /v1/tasks	All four use the same request format; switch models by changing one field.

When to Use Which

Blog and social images

FLUX.1 [schnell] keeps costs tiny when you need lots of images quickly.

Product and lifestyle shots

Z-Image's photoreal output suits mockups, ads and catalog drafts.

Chinese content

Seedream 5.0 Flash understands Chinese prompts and renders Chinese text more reliably.

Prototyping

Try layouts and concepts cheaply before committing to a premium model.

Batch generation

At $0.00143-0.025 per image, large batches stay affordable through the API.

Need more quality?

Step up to GPT Image or Nano Banana for complex scenes and precise editing.

Tips for Budget Models

Be concrete

Name the subject, setting, light and style. Budget models reward specific prompts.

Keep text short

If you need words in the image, keep them to a few and put them in quotes.

Use the same prompt to compare

Change only the model so the comparison is fair.

Pick the right ratio

Z-Image and FLUX.2 [klein] 4B support wide and tall formats; FLUX.1 [schnell] returns 4:3 landscape images, and Seedream 5.0 Flash picks the ratio from your prompt.

Write prompts faster

Use the AI Image Prompt Generator to expand a short idea into a full prompt.

Scale through the API

Once you've picked a model, batch it through the API instead of clicking.

Free Tool vs Playground vs API

Use the free tool to compare models with the same prompt, then pick a signed-in workflow for higher quality or automation.

Option	Access	Output and workflow	Best for
Free	No account or API key; up to 5 images across all models in a rolling 24-hour period.	Model-dependent output sizes, with a subtle hiapi.ai text watermark.	Comparing models and testing prompts.
Playground	Account required; usage-based paid generation runs directly in the browser.	More aspect ratios and resolution or quality controls, depending on the selected route, plus generation history.	Higher-control creator workflows.
API	Account and hiAPI key required; usage-based API pricing.	Programmatic task submission, polling or callbacks, and production integration.	Apps, automations, and developer workflows.

HiAPI Image Generation API for Developers

One API key for FLUX, Z-Image, Seedream, GPT Image, Nano Banana and more. Pay per image, no subscription.

Free AI Image Models FAQ

Is this AI image generator free?

Yes. No sign-up. You get 5 free images every 24 hours across all four models, and failed generations don't count.

Why is there a watermark?

Free previews carry a small hiapi.ai mark. Open the same prompt in the model playground or use the API for clean, full-quality images.

Which model is cheapest?

FLUX.2 [klein] 4B, at $0.00143 per image through the HiAPI API. FLUX.1 [schnell] is $0.005, Z-Image is $0.008 and Seedream 5.0 Flash is $0.025.

Can I use GPT Image or Nano Banana for free?

They have their own free pages. This page focuses on the lowest-cost models so you can compare budget options.

Are my prompts or images stored?

Prompts are sent to the model only to create your image. This page doesn't keep your images; HiAPI stores generated results temporarily and they expire after about 7 days, so download the ones you want to keep.

How do I use these models in my app?

Create a HiAPI API key and send POST /v1/tasks with the model name and your prompt, then fetch the result. The same key works for every model.

Need the full parameter reference? Browse image models · View usage pricing · Read the HiAPI task API documentation