No free plan. The cheapest way in is Open Weights (Self-Host) at Free model weights (infrastructure costs apply). Consider free alternatives in the automation & workflows category if budget is tight.
Jamba is a hybrid of Mamba (a state-space model) and Transformer attention layers, with a mixture-of-experts component in the larger variants. Mamba layers scale linearly with sequence length instead of quadratically, which is why Jamba can handle a 256K context window at much lower latency and memory cost than a pure Transformer of similar quality.
Yes. AI21 publishes open weights for Jamba Mini and Jamba Large on Hugging Face under an open-model license, and provides guidance for VPC, on-prem, and air-gapped deployment. This is one of the main reasons regulated industries choose Jamba over closed-only API models.
Claude and Gemini have larger headline context windows and stronger reasoning, but they are closed APIs and typically cost more per token. Jamba's advantage is cost-per-token and throughput at long context, plus the ability to deploy the weights inside your own environment. If you need frontier reasoning, Claude or Gemini usually win; if you need to cheaply read a lot of text inside a VPC, Jamba is often the better pick.
Long-context, grounded enterprise workloads: contract and legal document review, financial report analysis, RAG over large knowledge bases, compliance monitoring, support-ticket triage, and agentic pipelines that need to keep a lot of retrieved context in the prompt.
Through AI21 Studio directly, through AWS Bedrock, Azure AI, Google Vertex AI, Snowflake Cortex, and Databricks, and as open weights on Hugging Face for self-hosting. Enterprise customers can also get dedicated deployments with fine-tuning and solution-engineering support from AI21.
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Last verified March 2026