kitio.aiOpenAI API vs Z.ai API
A side-by-side look at pricing plans, free tiers, features, pros and cons, updated for 2026. OpenAI API starts at See pricing page and Z.ai API starts at See pricing page. Check both pricing pages for current plans.
At a glance
Best for
Category
Pricing model
Starting price
Free plan
Made by
Based in
Rating
Key features
- Responses API
- Agents SDK
- Realtime voice API
- Image and audio models
- Batch API
- Fine-tuning and evals
- GLM flagship and Flash models
- OpenAI-compatible API
- GLM Coding Plans
- Vision models
- Tool calling
| Feature | OpenAI API | Z.ai API |
|---|---|---|
| Best for | Developer API for GPT, reasoning, image, audio and embedding models | Pay-per-token API and coding plans for Zhipu's GLM models |
| Category | Models & APIs | Models & APIs |
| Pricing model | Paid | Paid |
| Starting price | See pricing page | See pricing page |
| Free plan | No | No |
| Made by | OpenAI | Z.ai (formerly Zhipu AI) |
| Based in | United States | China |
| Rating | No ratings yet | No ratings yet |
| Key features |
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Pricing compared
OpenAI API starts at See pricing page and Z.ai API starts at See pricing page. Check both pricing pages for current plans.
Free plan
Cheapest paid plan
Top plan
Free trial
3 plans
GPT-6 Luna
$0.10 / $0.50 per 1M tokens
- Input / output
- Fast, low-cost model
- 1.05M context
GPT-6.1 Sol
$2 / $10 per 1M tokens
- Input / output
- Balanced model
- 1.05M context
GPT-6 Astra
$10 / $50 per 1M tokens
- Input / output
- Most capable model
- 1.05M context
Prices in USD, checked Oct 28, 2026 or later. Plans change often, so confirm on each tool's site before you buy.
Pros and cons
OpenAI API
- Wide model range in one API
- Mature SDKs and docs
- Built-in tools like web search
- Top models are costly at scale
- Rate limits depend on spend tier
- Model names change frequently
Z.ai API
- Low cost for strong coding models
- Fixed-price coding plans
- Open weights released
- Less known outside developer circles
- Data processed in China
- Docs can lag releases
Which one should you choose?
Choose OpenAI API if you want:
- Wide model range in one API
- Mature SDKs and docs
- Built-in tools like web search
Watch out: top models are costly at scale.
Choose Z.ai API if you want:
- Low cost for strong coding models
- Fixed-price coding plans
- Open weights released
Watch out: less known outside developer circles.
OpenAI API vs Z.ai API FAQ
What is the difference between OpenAI API and Z.ai API?
OpenAI API: Developer API for GPT, reasoning, image, audio and embedding models. Z.ai API: Pay-per-token API and coding plans for Zhipu's GLM models. Both are models & apis tools.
Is OpenAI API or Z.ai API cheaper?
OpenAI API starts at See pricing page and Z.ai API starts at See pricing page. Check both pricing pages for current plans.
Do OpenAI API and Z.ai API have free plans?
OpenAI API: No. Z.ai API: No.
Who makes OpenAI API?
OpenAI API is made by OpenAI, based in United States.
Who makes Z.ai API?
Z.ai API is made by Z.ai (formerly Zhipu AI), based in China.
Which should I choose, OpenAI API or Z.ai API?
Choose OpenAI API if you value wide model range in one api and mature sdks and docs. Choose Z.ai API if you value low cost for strong coding models and fixed-price coding plans.