AI21 Labs

AI21 Labs is an Israeli AI company that builds the Jamba family of language models for enterprise use. Jamba combines Mamba state space layers with Transformer attention in one hybrid design, which AI21 says makes long inputs faster and cheaper to process. Every Jamba model supports a context window of 256,000 tokens, which AI21 describes as the longest among open models.

The documentation lists three current models. Jamba Large has 398 billion parameters with 94 billion active, version 1.7 from July 2025, and is served at the jamba large endpoint. Jamba Mini 2 has 52 billion parameters with 12 billion active, from a January 2026 snapshot, served at jamba mini. Jamba 3B is a compact three billion parameter model aimed at running on devices and supporting agent systems, and it has no hosted endpoint. Input and output are text only, and the models officially support nine languages: English, Spanish, French, Portuguese, Italian, Dutch, German, Arabic and Hebrew.

AI21's main pitch is private deployment. Because the weights can be downloaded, companies can run Jamba inside their own virtual private cloud, entirely on premises, or in a hybrid setup, so the vendor never sees their data. AI21 positions this for finance, healthcare and other regulated work, and lists SOC 2 compliance plus ISO 27001, 27017 and 27018 certifications.

Developers who prefer a hosted service can call Jamba through the AI21 Studio API and test it in the Studio Playground. AI21 advises pinning dated model versions, such as jamba-large-1.7-2025-07, to avoid surprises when the default alias moves to a new snapshot. Older 1.5 and 1.6 versions have already been retired.

The docs also list known limits: a knowledge cutoff in 2024, possible inconsistency in long answers, and a bias toward English text. For a broader look at paid and free model APIs, see our guide to free OpenAI API alternatives.