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GPT-5 nano vs Jamba 1.5 Mini

A complete head-to-head: pricing, context window, benchmarks, modality coverage, and openness, with a programmatic verdict synthesized from the underlying data.

Updated

GPT-5 nano specs · Jamba 1.5 Mini specs
Verdict by category
  • PriceTie

    Both land near $0.40 / 1M output tokens, call it a wash on cost.

  • Context windowGPT-5 nano

    GPT-5 nano accepts 400K tokens vs 256K, 1.6× 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-5 nano

    GPT-5 nano supports 2 modalities (text, vision) vs 1 for Jamba 1.5 Mini.

  • OpennessJamba 1.5 Mini

    Jamba 1.5 Mini ships open weights (Jamba Open Model License); GPT-5 nano is API-only.

On balance GPT-5 nano edges ahead, winning 2 of 5 categories against Jamba 1.5 Mini's 1. Both land near $0.40 / 1M output tokens, call it a wash on cost. GPT-5 nano accepts 400K tokens vs 256K, 1.6× 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-5 nano handles text, vision while Jamba 1.5 Mini handles text, which can be the deciding factor before you even look at benchmarks. Jamba 1.5 Mini ships open weights (Jamba Open Model License); GPT-5 nano is API-only.

GPT-5 nano is the newer of the two, released 12 months after Jamba 1.5 Mini, which usually means a more recent knowledge cutoff and updated safety post-training. GPT-5 nano is usually picked for cheapest llm and fastest llm workloads, while Jamba 1.5 Mini sees more deployments in long context and summarization. If pricing matters more than every last benchmark point, run the numbers in the calculator below before committing.

Side-by-side specs

SpecGPT-5 nanoJamba 1.5 Mini
ProviderOpenAIAI21
ReleasedAug 2025Aug 2024
Modalitiestext, visiontext
Context window400K tokens256K tokens
Max output128K tokens,
Input · 1M$0.050 / 1M tokens$0.20 / 1M tokens
Output · 1M$0.40 / 1M tokens$0.40 / 1M tokens
Knowledge cutoff2024-09,
Open weightsNoYes (Jamba Open Model License)
API availableYesYes

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$0.750 vs $1.20
  • Heavy usage, 1M in / 500k out per day$7.50 vs $12.00
  • RAG workload, 5M in / 200k out per day$9.90 vs $32.40

Light usage, 100k in / 50k out per day: $0.750 vs $1.20 per month, model A comes out ahead. Heavy usage, 1M in / 500k out per day: $7.50 vs $12.00 per month, model A comes out ahead. RAG workload, 5M in / 200k out per day: $9.90 vs $32.40 per month, model A comes out ahead.

Price calculator

Estimated spend for the listed models at your usage. Numbers are derived from each model's published per-million-token rates.

  • GPT-5 nano$0.025
  • Jamba 1.5 Mini$0.040

Benchmarks compared

Only sourced numbers. Where a benchmark is missing for one model we show the available value rather than fabricating the other.

Benchmark scores not yet available. We only publish numbers we can source from official model cards or independent leaderboards, see methodology.
Pick GPT-5 nano if

GPT-5 nano fits when…

  • Lowest-cost OpenAI model with vision support
  • Fast P99 latency
  • Good enough for routing and classification
  • Long-context tasks, handles 400K tokens vs 256K for Jamba 1.5 Mini.
  • Multimodal needs covering vision.
Pick Jamba 1.5 Mini if

Jamba 1.5 Mini fits when…

  • 256k context at small-model price
  • Hybrid SSM-Transformer is efficient on long inputs
  • Open weights for self-hosting
  • Self-hosting and on-prem requirements, open weights (Jamba Open Model License).
Don't want either?

Consider GPT-5.5

OpenAI's mid-cycle GPT-5 refresh, improved reasoning, tool use, and multimodal grounding over the 2025 launch.

See GPT-5.5 specsGPT-5 nano vs GPT-5.5Jamba 1.5 Mini vs GPT-5.5

Frequently asked

  • Is GPT-5 nano or Jamba 1.5 Mini cheaper?
    Both GPT-5 nano and Jamba 1.5 Mini are priced equivalently at $0.40 / 1M tokens per million output tokens.
  • Which has the larger context window?
    GPT-5 nano accepts 400K tokens vs 256K for Jamba 1.5 Mini.
  • Is GPT-5 nano or Jamba 1.5 Mini better for coding?
    Both GPT-5 nano and Jamba 1.5 Mini 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 Mini ships open weights (Jamba Open Model License). GPT-5 nano is API-only.
  • When were GPT-5 nano and Jamba 1.5 Mini released?
    GPT-5 nano was released by OpenAI on 2025-08-07. Jamba 1.5 Mini was released by AI21 on 2024-08-22.
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