BenchLeader

Jamba 1.5 Mini

Jamba 1.5 Mini is an AI21 Labs open-weights model, released 22 Aug 2024. Its best configuration ranks #734 of 785 on the BenchLeader Index at 37.3 ±7.4, in the lower half. The ± is the point: 258 other configurations score within that range, so they and this one cannot be told apart on quality alone — price and speed are what separate them. It scores highest in human preference (38) and lowest in knowledge (18). At $0.250 per million tokens blended it is cheaper than most ranked models. Last measured 22 Oct 2026.

Blended price
$0.250/M
$0.200 in · $0.400 out
Output speed
–
First answer
–
Context
256k
Full answer
–
Cost per run
–
Released
22 Aug 2024
How it scores by categoryDashed line = average model (50). One step of 15 = one standard deviation.
  1. Overall index37
  2. Reasoning37
  3. Coding37
  4. Maths34
  5. Knowledge18
  6. Human preference38
  7. Composite35

Versions

AI21 Labs has shipped 5 models under this name. Each is ranked on its own results; a newer version often has fewer results so far, which holds its index nearer the average until more arrive.

ModelReleasedIndexRank
Jamba Mini8 Jan 2026––
Jamba 1.7 Mini7 Jul 202539.5#685
Jamba 1.5 Minithis page22 Aug 202437.3#734
Jamba Mini 1.6–21.8#785
Jamba Mini 1.7–––

How its index has moved

9 Sept 2026 to 21 Oct 2026
303845

The index is recomputed from scratch every day, so a line moves when a new benchmark result lands, when a publisher revises a score, or when the models it is normalised against change. Early movement usually means the score is still settling.

Benchmark results

See all LLM benchmarks. One column per reasoning effort. Rank is among every configuration of every model on that benchmark. Hover a score for the run it came from.

Reasoning

Benchmarknot statedSourceTrend
Arena Hard Prompts1237#296Arena (LMArena)
GPQA Diamond (AA)not in index30.2%#521Artificial Analysis
Humanity's Last Exam (AA)not in index5.1%#443Artificial Analysis

Coding

Benchmarknot statedSourceTrend
Arena Coding1264#298Arena (LMArena)

Maths

Benchmarknot statedSourceTrend
Arena Maths1187#308Arena (LMArena)

Knowledge

Benchmarknot statedSourceTrend
LegalBench66.6%#129Vals AI
CorpFin33.9%#122Vals AI
TaxEval41.9%#136Vals AI
MedQA55.2%#85Vals AI

Instruction following

Benchmarknot statedSourceTrend
Arena Instruction Followingnot in index1205#300Arena (LMArena)

Human preference

Benchmarknot statedSourceTrend
Arena Text1240#292Arena (LMArena)
Arena Creative Writingnot in index1211#284Arena (LMArena)
Arena Multi-turnnot in index1205#296Arena (LMArena)
Arena Longer Queriesnot in index1218#305Arena (LMArena)

Composite

Benchmarknot statedSourceTrend
AA Intelligence Index v4.3.25.2#596Artificial Analysis

What a task costs

Estimates from list price, output speed and time to first answer for the best configuration. “With caching” assumes three-quarters of the input is served from the prompt cache. Reasoning tokens are not modelled.

WorkloadTokens in / outCostWith cachingTime
Chat reply400 / 300$0.0002––
Summarize a 30-page report12,000 / 600$0.0026––
Code edit6,000 / 1,500$0.0018––
Agentic coding session60,000 / 4,000$0.014––
Structured extraction2,000 / 200$0.0005––

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See also

Questions people ask

What are Jamba 1.5 Mini's benchmark scores?
As of 25 Oct 2026, Jamba 1.5 Mini scores 37.3 ±7.4 on the BenchLeader Index, strongest in human preference (38) and weakest in knowledge (18). That rests on 9 independent benchmark results, and every score on this page links to its publisher.
How does Jamba 1.5 Mini rank?
Jamba 1.5 Mini is #734 of 785 ranked configurations on 25 Oct 2026. 258 other configurations score within its margin, so the exact position matters less than the band. The leader is Claude Opus 5.5 (max effort) at 72.6.
How much does Jamba 1.5 Mini cost per 1M tokens?
As of 25 Oct 2026, Jamba 1.5 Mini costs $0.200 per 1M input tokens and $0.400 per 1M output tokens, $0.250 blended (three input tokens per output token).
When was Jamba 1.5 Mini released?
AI21 Labs released Jamba 1.5 Mini on 22 Aug 2024.

Data as of 25 Oct 2026. Compare with another model.

Cite as: BenchLeader, “Jamba 1.5 Mini: benchmarks, pricing, speed and rank”, data as of 25 Oct 2026, https://www.benchleader.com/models/jamba-1-5-mini.