GPT-4.1 vs Jamba 1.5 Large
A complete head-to-head: pricing, context window, benchmarks, modality coverage, and openness, with a programmatic verdict synthesized from the underlying data.
Updated
GPT-4.1 specs · Jamba 1.5 Large specs- PriceTie
Both land near $8.00 / 1M output tokens, call it a wash on cost.
- Context windowGPT-4.1
GPT-4.1 accepts 1M tokens vs 256K, 3.9× the room for long documents and codebases.
- BenchmarksTie
No directly comparable public benchmarks are available for both models, check the spec sheets for individual scores.
- ModalitiesGPT-4.1
GPT-4.1 supports 2 modalities (text, vision) vs 1 for Jamba 1.5 Large.
- OpennessJamba 1.5 Large
Jamba 1.5 Large ships open weights (Jamba Open Model License); GPT-4.1 is API-only.
On balance GPT-4.1 edges ahead, winning 2 of 5 categories against Jamba 1.5 Large's 1. Both land near $8.00 / 1M output tokens, call it a wash on cost. GPT-4.1 accepts 1M tokens vs 256K, 3.9× the room for long documents and codebases.
No directly comparable public benchmarks are available for both models, check the spec sheets for individual scores. They differ in modality coverage, GPT-4.1 handles text, vision while Jamba 1.5 Large handles text, which can be the deciding factor before you even look at benchmarks. Jamba 1.5 Large ships open weights (Jamba Open Model License); GPT-4.1 is API-only.
GPT-4.1 is the newer of the two, released 8 months after Jamba 1.5 Large, which usually means a more recent knowledge cutoff and updated safety post-training. GPT-4.1 is usually picked for long context and rag workloads, while Jamba 1.5 Large sees more deployments in long context and rag. If pricing matters more than every last benchmark point, run the numbers in the calculator below before committing.
Side-by-side specs
| Spec | GPT-4.1 | Jamba 1.5 Large |
|---|---|---|
| Provider | OpenAI | AI21 |
| Released | Apr 2025 | Aug 2024 |
| Modalities | text, vision | text |
| Context window | 1M tokens | 256K tokens |
| Max output | 32.8K tokens | , |
| Input · 1M | $2.00 / 1M tokens | $2.00 / 1M tokens |
| Output · 1M | $8.00 / 1M tokens | $8.00 / 1M tokens |
| Knowledge cutoff | 2024-06 | , |
| Open weights | No | Yes (Jamba Open Model License) |
| API available | Yes | Yes |
Pricing at scale
What you'd actually pay at typical workloads. Numbers come from each model's published per-million-token rates.
- Light usage, 100k in / 50k out per day$18.00 vs $18.00
- Heavy usage, 1M in / 500k out per day$180 vs $180
- RAG workload, 5M in / 200k out per day$348 vs $348
Light usage, 100k in / 50k out per day: both models cost about $18.00 a month, call it a tie. Heavy usage, 1M in / 500k out per day: both models cost about $180 a month, call it a tie. RAG workload, 5M in / 200k out per day: both models cost about $348 a month, call it a tie.
Estimated spend for the listed models at your usage. Numbers are derived from each model's published per-million-token rates.
- GPT-4.1$0.600
- Jamba 1.5 Large$0.600
Benchmarks compared
Only sourced numbers. Where a benchmark is missing for one model we show the available value rather than fabricating the other.
- MMLU86.2
- HumanEval90.6
GPT-4.1 fits when…
- 1M-token context window, strong for long-doc workloads
- Mature SDK and tooling integrations
- Reliable JSON-mode and function-calling
- Long-context tasks, handles 1M tokens vs 256K for Jamba 1.5 Large.
- Multimodal needs covering vision.
Jamba 1.5 Large fits when…
- 256k context
- Efficient long-context inference
- Open weights
- Self-hosting and on-prem requirements, open weights (Jamba Open Model License).
Consider GPT-5.5
OpenAI's mid-cycle GPT-5 refresh, improved reasoning, tool use, and multimodal grounding over the 2025 launch.
Frequently asked
Is GPT-4.1 or Jamba 1.5 Large cheaper?
Both GPT-4.1 and Jamba 1.5 Large are priced equivalently at $8.00 / 1M tokens per million output tokens.Which has the larger context window?
GPT-4.1 accepts 1M tokens vs 256K for Jamba 1.5 Large.Is GPT-4.1 or Jamba 1.5 Large better for coding?
Both GPT-4.1 and Jamba 1.5 Large are competitive on coding benchmarks. See each model's individual spec page for HumanEval and SWE-bench scores where published. For an opinionated pick, consult our Best LLM for Coding ranking.Are either of these models open source?
Jamba 1.5 Large ships open weights (Jamba Open Model License). GPT-4.1 is API-only.When were GPT-4.1 and Jamba 1.5 Large released?
GPT-4.1 was released by OpenAI on 2025-04-14. Jamba 1.5 Large was released by AI21 on 2024-08-22.
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