Model

AI21 Jamba 1.5 Mini

OPEN

AI21 Labs · AI21 Jamba family · released Aug 22, 2024

Open hybrid SSM-Transformer, 12B/52B active/total, 256K context under the Jamba Open Model License; strongest Arena-Hard score in its class.

ReasoningCodingVisionFunction callingTool useAgentic

508.6

Elo · rank #308

Parameters

52B

Active params

12B (MoE)

Context

256K tokens

Architecture

Hybrid Mamba-Transformer MoE (Jamba)

License

Jamba Open Model License

Languages

API price (in/out)

$0.2 / $0.4

Modalities

text

Benchmark results

Bar shows position within the tracked field; marker = field best

ARC-ChallengeReasoning85.7%#30

best: Llama 3.1 405B · 96.9%

Arena-HardHuman preference46.1%#44

best: Qwen3-235B-A22B (Non-Thinking) · 96.1%

BIG-Bench HardReasoning53.4%#92

best: ERNIE 4.5 300B-A47B · 94.3%

BFCLAgents80.7%#11

best: SmolLM3 3B (No Thinking) · 92.3%

GPQA DiamondReasoning32.3%#260

best: GPT-6 Astra · 96.0%

GSM8KMath75.8%#91

best: Llama 3.1 405B · 96.8%

HumanEvalCoding62.8%#95

best: Claude Opus 4.5 · 99.4%

IFEvalReasoning75.8%#104

best: Gemma 4 26B A4B · 98.5%

MMLU-ProKnowledge39.8%#152

best: Claude Fable 5 · 91.5%

MMLUKnowledge69.7%#146

best: OpenAI o3 · 92.9%

MMMLUKnowledge64.3%#49

best: Gemini 3.1 Pro · 92.6%

TruthfulQAKnowledge54.1%#41

best: Phi-3.5-MoE (16x3.8B, 6.6B active) · 77.5%

WildBenchHuman preference42.4%#7

best: Mistral Small 3.2 (24B) · 65.3%

Run it locally

VRAM @ Q4

29.5 GB

VRAM @ FP16

103.2 GB

Fits on (Q4)

RTX 5090 32GBM4 Pro 48GBM3 Max 128GBM3 Ultra 512GBA100 80GBH100 80GBH200 141GBB200 192GB

Throughput data unavailable.

Quantizations

GGUF Q4

Fine-tune it

Conditional / custom

QLoRA35.4 GB1× A100 80GB

LoRA110.8 GB1× H200 141GB

Full fine-tune834.6 GB8× H200 141GB

QLoRA SFT on ~10k samples ≈ $36.57 (1× A100 80GB)

Plan a fine-tune →

AI21 Jamba family

Elo progression across releases

AI21 JambaMar 2024224.3 AI21 Jamba 1.5 LargeAug 2024736.1 AI21 Jamba 1.5 MiniAug 2024508.6

Resources

HFai21labs/AI21-Jamba-Mini-1.5 DOCSdocs.ai21.com APIAvailable via AI21 Labs API

API price $0.2/$0.4 · each benchmark row carries its own source badge (see methodology)