kitio.aiZ.ai API vs AI21
A side-by-side look at pricing plans, free tiers, features, pros and cons, updated for 2026. Z.ai API starts at See pricing page and AI21 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
- GLM flagship and Flash models
- OpenAI-compatible API
- GLM Coding Plans
- Vision models
- Tool calling
- Jamba Mini and Jamba Large APIs
- Long-context models
- Custom post-training
- Python SDK
- Free trial credits
| Feature | Z.ai API | AI21 |
|---|---|---|
| Best for | Pay-per-token API and coding plans for Zhipu's GLM models | Jamba model APIs and custom post-training for enterprises |
| Category | Models & APIs | Models & APIs |
| Pricing model | Paid | Free trial |
| Starting price | See pricing page | See pricing page |
| Free plan | No | No, 7-day trial |
| Made by | Z.ai (formerly Zhipu AI) | AI21 Labs |
| Based in | China | Israel |
| Rating | No ratings yet | No ratings yet |
| Key features |
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Pricing compared
Z.ai API starts at See pricing page and AI21 starts at See pricing page. Check both pricing pages for current plans.
Free plan
Cheapest paid plan
Top plan
Free trial
3 plans
Jamba Mini
$0.2 / 1M input tokens
- $0.4 per 1M output tokens
- Lightweight general model
Jamba Large
$2 / 1M input tokens
- $8 per 1M output tokens
- Long-context model
Custom
Contact sales
- Volume discounts
- Dedicated account manager
- Priority support
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
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
AI21
- Low per-token price on Jamba Mini
- Long context windows
- Customer owns its post-trained model
- Trial credits expire after 7 days
- Smaller ecosystem than larger model labs
- Post-training requires a sales process
Which one should you choose?
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.
Choose AI21 if you want:
- Low per-token price on Jamba Mini
- Long context windows
- Customer owns its post-trained model
Watch out: trial credits expire after 7 days.
Z.ai API vs AI21 FAQ
What is the difference between Z.ai API and AI21?
Z.ai API: Pay-per-token API and coding plans for Zhipu's GLM models. AI21: Jamba model APIs and custom post-training for enterprises. Both are models & apis tools.
Is Z.ai API or AI21 cheaper?
Z.ai API starts at See pricing page and AI21 starts at See pricing page. Check both pricing pages for current plans.
Do Z.ai API and AI21 have free plans?
Z.ai API: No. AI21: No, 7-day trial.
Who makes Z.ai API?
Z.ai API is made by Z.ai (formerly Zhipu AI), based in China.
Who makes AI21?
AI21 is made by AI21 Labs, based in Israel.
Which should I choose, Z.ai API or AI21?
Choose Z.ai API if you value low cost for strong coding models and fixed-price coding plans. Choose AI21 if you value low per-token price on jamba mini and long context windows.