Choose AI21: Jamba Large 1.7 if…
- cost matters at scale — it is 88% cheaper on a typical 3:1 input/output mix ($310 vs $2,468 a month for 50,000 support chats)
Neither wins outright: AI21: Jamba Large 1.7 is the pick when cost matters at scale, OpenAI: GPT-5.2 Pro (batch) when you need to fit long inputs in one request.
| Spec | AI21: Jamba Large 1.7 | OpenAI: GPT-5.2 Pro (batch) |
|---|---|---|
| Provider | AI21 | OpenAI |
| Input price (per 1M tokens) | $2.00 | $10.50 |
| Output price (per 1M tokens) | $8.00 | $84.00 |
| Blended price (3:1 input/output) | $3.50 | $28.88 |
| Cheaper than … of all models we track | 18% | 2% |
| Context window | 256K tokens (~384 pages) | 400K tokens (~600 pages) |
| Larger context than … of all models | 45% | 63% |
| Max output per response | 4K tokens (~3,100 words) | 128K tokens (~96,000 words) |
| Input types | text | image, text, file |
| Output types | text | text |
| Free variant | No | No |
| Listed since | 2025-08-08 | 2025-12-10 |
Monthly cost at list price for five common workloads. Token counts per unit are stated so you can scale them to your own traffic. A workload that does not fit a model's context window is marked rather than priced.
| Workload (per month) | AI21: Jamba Large 1.7 | OpenAI: GPT-5.2 Pro (batch) | Difference |
|---|---|---|---|
| Customer-support chatbot 50,000 conversations — each a 6-turn conversation (1,500 in / 400 out tokens) | $310 | $2,468 | AI21: Jamba Large 1.7 saves $2,158 |
| RAG search over documents 20,000 questions — each a question answered from ~8 retrieved passages (6,000 in / 500 out tokens) | $320 | $2,100 | AI21: Jamba Large 1.7 saves $1,780 |
| Coding / tool-using agent 2,000 tasks — each a multi-step task with tool calls and file context (60,000 in / 6,000 out tokens) | $336 | $2,268 | AI21: Jamba Large 1.7 saves $1,932 |
| Batch summarisation 10,000 documents — each a 6,000-word report summarised to a page (8,000 in / 600 out tokens) | $208 | $1,344 | AI21: Jamba Large 1.7 saves $1,136 |
| Long-document analysis 500 documents — each a 150-page contract or codebase read in one pass (100,000 in / 2,000 out tokens) | $108 | $609 | AI21: Jamba Large 1.7 saves $501 |
| Capability | AI21: Jamba Large 1.7 | OpenAI: GPT-5.2 Pro (batch) | What it lets you do |
|---|---|---|---|
| Tool / function calling | ✓ Yes | ✓ Yes | call your APIs and run agent loops |
| Structured output (JSON schema) | ✓ Yes | ✓ Yes | return JSON that validates against your schema |
| Reasoning / thinking mode | — | ✓ Yes | spend extra tokens thinking before answering hard problems |
| Image input | — | ✓ Yes | read screenshots, charts and scanned pages |
| Audio input | — | — | take speech or audio directly |
| File / PDF input | — | ✓ Yes | accept documents without your own parsing step |
| Image output | — | — | generate images, not just text |
| Built-in web search | — | ✓ Yes | answer from live web results |
| Seed (reproducible sampling) | — | ✓ Yes | repeat a generation for tests and evals |
| Log-probabilities | — | — | read token confidence for classification and scoring |
From each model's published parameters and input/output types. “—” means not advertised, not proven absent.
Neither wins outright: AI21: Jamba Large 1.7 is the pick when cost matters at scale, OpenAI: GPT-5.2 Pro (batch) when you need to fit long inputs in one request. In short: AI21: Jamba Large 1.7 when cost matters at scale; OpenAI: GPT-5.2 Pro (batch) when you need to fit long inputs in one request, you need reasoning / thinking mode, you need image input, you need file / PDF input, you need built-in web search, you need seed (reproducible sampling), you generate long outputs in one go, you want the newer model.
AI21: Jamba Large 1.7 is cheaper: $3.50 vs $28.88 per 1M tokens at a typical 3:1 input/output mix, 88% less. For 50,000 support conversations a month that is $310 against $2,468.
AI21: Jamba Large 1.7 costs $2.00 per 1M input tokens and $8.00 per 1M output tokens; OpenAI: GPT-5.2 Pro (batch) costs $10.50 input and $84.00 output. Output tokens are billed separately, so long answers shift the gap.
OpenAI: GPT-5.2 Pro (batch): 400K tokens, about 600 pages, against 256K (about 384 pages) for AI21: Jamba Large 1.7.
Tool calling — AI21: Jamba Large 1.7: yes, OpenAI: GPT-5.2 Pro (batch): yes. JSON-schema structured output — AI21: Jamba Large 1.7: yes, OpenAI: GPT-5.2 Pro (batch): yes.
Only OpenAI: GPT-5.2 Pro (batch) accepts image input; AI21: Jamba Large 1.7 is text-only for input.
No free variant is listed for either; both are pay-per-token.
AI21: Jamba Large 1.7 can write up to 4K tokens (about 3,100 words) per response; OpenAI: GPT-5.2 Pro (batch) up to 128K (about 96,000 words).
AI21: Jamba Large 1.7 was listed on 2025-08-08; OpenAI: GPT-5.2 Pro (batch) on 2025-12-10.
Jamba Large 1.7 is the latest model in the Jamba open family, offering improvements in grounding, instruction-following, and overall efficiency. Built on a hybrid SSM-Transformer architecture with a 256K context...
Full AI21: Jamba Large 1.7 specs →GPT-5.2 Pro is OpenAI’s most advanced model, offering major improvements in agentic coding and long context performance over GPT-5 Pro. It is optimized for complex tasks that require step-by-step reasoning,...
Full OpenAI: GPT-5.2 Pro (batch) specs →