kitio.aiOpenAI API vs AI21
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 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
- Responses API
- Agents SDK
- Realtime voice API
- Image and audio models
- Batch API
- Fine-tuning and evals
- Jamba Mini and Jamba Large APIs
- Long-context models
- Custom post-training
- Python SDK
- Free trial credits
| Feature | OpenAI API | AI21 |
|---|---|---|
| Best for | Developer API for GPT, reasoning, image, audio and embedding 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 | OpenAI | AI21 Labs |
| Based in | United States | Israel |
| Rating | No ratings yet | No ratings yet |
| Key features |
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Pricing compared
OpenAI 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
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
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
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
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 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 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.
OpenAI API vs AI21 FAQ
What is the difference between OpenAI API and AI21?
OpenAI API: Developer API for GPT, reasoning, image, audio and embedding models. AI21: Jamba model APIs and custom post-training for enterprises. Both are models & apis tools.
Is OpenAI API or AI21 cheaper?
OpenAI API starts at See pricing page and AI21 starts at See pricing page. Check both pricing pages for current plans.
Do OpenAI API and AI21 have free plans?
OpenAI API: No. AI21: No, 7-day trial.
Who makes OpenAI API?
OpenAI API is made by OpenAI, based in United States.
Who makes AI21?
AI21 is made by AI21 Labs, based in Israel.
Which should I choose, OpenAI API or AI21?
Choose OpenAI API if you value wide model range in one api and mature sdks and docs. Choose AI21 if you value low per-token price on jamba mini and long context windows.