Choose AI21: Jamba Large 1.7 if…
No advantage on the data we track — pick it for provider preference or output quality on your own prompts.
AI21: Jamba Large 1.7 vs Z.ai: GLM 5.3 Flash
Z.ai: GLM 5.3 Flash comes out ahead on the data we track: 8 advantages and none for AI21: Jamba Large 1.7.
Key numbers
| Spec | AI21: Jamba Large 1.7 | Z.ai: GLM 5.3 Flash |
|---|---|---|
| Provider | AI21 | Z Ai |
| Input price (per 1M tokens) | $2.00 | $0.15 |
| Output price (per 1M tokens) | $8.00 | $0.50 |
| Blended price (3:1 input/output) | $3.50 | $0.24 |
| Cheaper than … of all models we track | 17% | 67% |
| Context window | 256K tokens (~384 pages) | 1.0M tokens (~1,573 pages) |
| Larger context than … of all models | 45% | 81% |
| Max output per response | 4K tokens (~3,100 words) | 944K tokens (~707,800 words) |
| Input types | text | text, image, video |
| Output types | text | text |
| Free variant | No | No |
| Listed since | 2025-08-08 | 2026-08-26 |
What it costs for real workloads
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 | Z.ai: GLM 5.3 Flash | Difference |
|---|---|---|---|
| Customer-support chatbot 50,000 conversations — each a 6-turn conversation (1,500 in / 400 out tokens) | $310 | $21.25 | Z.ai: GLM 5.3 Flash saves $289 |
| RAG search over documents 20,000 questions — each a question answered from ~8 retrieved passages (6,000 in / 500 out tokens) | $320 | $23.00 | Z.ai: GLM 5.3 Flash saves $297 |
| 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 | $24.00 | Z.ai: GLM 5.3 Flash saves $312 |
| Batch summarisation 10,000 documents — each a 6,000-word report summarised to a page (8,000 in / 600 out tokens) | $208 | $15.00 | Z.ai: GLM 5.3 Flash saves $193 |
| Long-document analysis 500 documents — each a 150-page contract or codebase read in one pass (100,000 in / 2,000 out tokens) | $108 | $8.00 | Z.ai: GLM 5.3 Flash saves $100 |
Capabilities side by side
| Capability | AI21: Jamba Large 1.7 | Z.ai: GLM 5.3 Flash | 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 | — | — | accept documents without your own parsing step |
| Image output | — | — | generate images, not just text |
| Built-in web search | — | — | answer from live web results |
| Seed (reproducible sampling) | — | ✓ Yes | repeat a generation for tests and evals |
| Log-probabilities | — | ✓ Yes | read token confidence for classification and scoring |
From each model's published parameters and input/output types. “—” means not advertised, not proven absent.
Price history
- AI21: Jamba Large 1.7: price unchanged since we started tracking it on 2026-03-10.
- Z.ai: GLM 5.3 Flash: input price raised 81% ($0.03 → $0.15/1M) on 2026-10-07 (10 price changes since 2026-08-27).
| Date | Model | Input / 1M | Output / 1M |
|---|---|---|---|
| 2026-10-07 | Z.ai: GLM 5.3 Flash | $0.15 | $0.50 |
| 2026-10-06 | Z.ai: GLM 5.3 Flash | $0.03 | $0.50 |
| 2026-09-28 | Z.ai: GLM 5.3 Flash | $0.15 | $0.50 |
| 2026-09-26 | Z.ai: GLM 5.3 Flash | $0.04 | $0.50 |
| 2026-09-25 | Z.ai: GLM 5.3 Flash | $0.04 | $0.60 |
| 2026-09-22 | Z.ai: GLM 5.3 Flash | $0.15 | $0.50 |
| 2026-09-17 | Z.ai: GLM 5.3 Flash | $0.09 | $0.30 |
| 2026-09-16 | Z.ai: GLM 5.3 Flash | $0.10 | $0.33 |
Which should you choose?
Choose Z.ai: GLM 5.3 Flash if…
- cost matters at scale — it is 93% cheaper on a typical 3:1 input/output mix ($21.25 vs $310 a month for 50,000 support chats)
- you need to fit long inputs in one request — 1.0M tokens is roughly 1,573 pages, against 384
- you need reasoning / thinking mode — to spend extra tokens thinking before answering hard problems; AI21: Jamba Large 1.7 does not advertise it
- you need image input — to read screenshots, charts and scanned pages; AI21: Jamba Large 1.7 does not advertise it
- you need seed (reproducible sampling) — to repeat a generation for tests and evals; AI21: Jamba Large 1.7 does not advertise it
- you need log-probabilities — to read token confidence for classification and scoring; AI21: Jamba Large 1.7 does not advertise it
- you generate long outputs in one go — up to 944K tokens (about 707,800 words) per response
- you want the newer model — released 2026-08-26, 13 months after the other
Frequently asked questions
Is AI21: Jamba Large 1.7 better than Z.ai: GLM 5.3 Flash?
Z.ai: GLM 5.3 Flash comes out ahead on the data we track: 8 advantages and none for AI21: Jamba Large 1.7.
Which is cheaper, AI21: Jamba Large 1.7 or Z.ai: GLM 5.3 Flash?
Z.ai: GLM 5.3 Flash is cheaper: $0.24 vs $3.50 per 1M tokens at a typical 3:1 input/output mix, 93% less. For 50,000 support conversations a month that is $21.25 against $310.
How much do AI21: Jamba Large 1.7 and Z.ai: GLM 5.3 Flash cost per million tokens?
AI21: Jamba Large 1.7 costs $2.00 per 1M input tokens and $8.00 per 1M output tokens; Z.ai: GLM 5.3 Flash costs $0.15 input and $0.50 output. Output tokens are billed separately, so long answers shift the gap.
Which has the bigger context window, AI21: Jamba Large 1.7 or Z.ai: GLM 5.3 Flash?
Z.ai: GLM 5.3 Flash: 1.0M tokens, about 1,573 pages, against 256K (about 384 pages) for AI21: Jamba Large 1.7.
Do AI21: Jamba Large 1.7 and Z.ai: GLM 5.3 Flash support function calling and JSON output?
Tool calling — AI21: Jamba Large 1.7: yes, Z.ai: GLM 5.3 Flash: yes. JSON-schema structured output — AI21: Jamba Large 1.7: yes, Z.ai: GLM 5.3 Flash: yes.
Can AI21: Jamba Large 1.7 or Z.ai: GLM 5.3 Flash read images?
Only Z.ai: GLM 5.3 Flash accepts image input; AI21: Jamba Large 1.7 is text-only for input.
Is AI21: Jamba Large 1.7 or Z.ai: GLM 5.3 Flash free to use?
No free variant is listed for either; both are pay-per-token.
What is the maximum output length of AI21: Jamba Large 1.7 and Z.ai: GLM 5.3 Flash?
AI21: Jamba Large 1.7 can write up to 4K tokens (about 3,100 words) per response; Z.ai: GLM 5.3 Flash up to 944K (about 707,800 words).
When were AI21: Jamba Large 1.7 and Z.ai: GLM 5.3 Flash released?
AI21: Jamba Large 1.7 was listed on 2025-08-08; Z.ai: GLM 5.3 Flash on 2026-08-26.
Has the price of AI21: Jamba Large 1.7 or Z.ai: GLM 5.3 Flash changed?
AI21: Jamba Large 1.7: price unchanged since we started tracking it on 2026-03-10. Z.ai: GLM 5.3 Flash: input price raised 81% ($0.03 → $0.15/1M) on 2026-10-07 (10 price changes since 2026-08-27).
About the two models
AI21: Jamba Large 1.7
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 →Z.ai: GLM 5.3 Flash
GLM-5.3-Flash is a native multimodal model from Z.ai. It is suited for efficient coding and long-horizon agent tasks. Its hybrid sparse and linear attention architecture maintains accurate long-context behavior while...
Full Z.ai: GLM 5.3 Flash specs →