Gemini 1.5 Flash vs Llama 3.1 8B Instruct
Gemini 1.5 Flash (2024) and Llama 3.1 8B Instruct (2024) are compact production models from Google DeepMind and AI at Meta. Gemini 1.5 Flash ships a 1M-token context window, while Llama 3.1 8B Instruct ships a 128K-token context window. On MMLU PRO, Gemini 1.5 Flash leads by 14.9 pts. On pricing, Llama 3.1 8B Instruct costs $0.02/1M input tokens versus $0.07/1M for the alternative. This comparison covers specs, pricing, capabilities, benchmarks, provider availability, and production fit.
Llama 3.1 8B Instruct is ~275% cheaper at $0.02/1M; pay for Gemini 1.5 Flash only for long-context analysis.
Decision scorecard
Local evidence first| Signal | Gemini 1.5 Flash | Llama 3.1 8B Instruct |
|---|---|---|
| Decision fit | RAG, Long context, and Classification | RAG, Long context, and Classification |
| Context window | 1M | 128K |
| Cheapest output | $0.3/1M tokens | $0.05/1M tokens |
| Provider routes | 2 tracked | 12 tracked |
| Shared benchmarks | MMLU PRO leader | 1 rows |
Decision tradeoffs
- Gemini 1.5 Flash leads the largest shared benchmark signal on MMLU PRO by 14.9 points.
- Gemini 1.5 Flash has the larger context window for long prompts, retrieval packs, or transcript analysis.
- Local decision data tags Gemini 1.5 Flash for RAG, Long context, and Classification.
- Llama 3.1 8B Instruct has the lower cheapest tracked output price at $0.05/1M tokens.
- Llama 3.1 8B Instruct has broader tracked provider coverage for fallback and procurement flexibility.
- Local decision data tags Llama 3.1 8B Instruct for RAG, Long context, and Classification.
Monthly cost at traffic
Estimate token spend from the cheapest tracked input and output prices on this page.
Gemini 1.5 Flash
$135
Cheapest tracked route: GCP Vertex AI
Llama 3.1 8B Instruct
$28.50
Cheapest tracked route: OpenRouter
Estimated monthly gap: $107. Batch, cache, and negotiated pricing are excluded from this local estimate.
Switch friction
- No overlapping tracked provider route is sourced for Gemini 1.5 Flash and Llama 3.1 8B Instruct; plan for SDK, billing, or endpoint changes.
- Llama 3.1 8B Instruct is $0.25/1M tokens lower on cheapest tracked output pricing before cache, batch, or negotiated discounts.
- No overlapping tracked provider route is sourced for Llama 3.1 8B Instruct and Gemini 1.5 Flash; plan for SDK, billing, or endpoint changes.
- Gemini 1.5 Flash is $0.25/1M tokens higher on cheapest tracked output pricing, so quality gains need to justify the spend.
Specs
| Specification | ||
|---|---|---|
| Released | 2024-05-14 | 2024-07-23 |
| Context window | 1M | 128K |
| Parameters | — | 8B |
| Architecture | decoder only | decoder only |
| License | Unknown | Open Source |
| Knowledge cutoff | - | - |
Pricing and availability
| Pricing attribute | Gemini 1.5 Flash | Llama 3.1 8B Instruct |
|---|---|---|
| Input price | $0.07/1M tokens | $0.02/1M tokens |
| Output price | $0.3/1M tokens | $0.05/1M tokens |
| Providers |
Capabilities
| Capability | Gemini 1.5 Flash | Llama 3.1 8B Instruct |
|---|---|---|
| Vision | No | No |
| Multimodal | No | No |
| Reasoning | No | No |
| Function calling | No | No |
| Tool use | No | No |
| Structured outputs | Yes | Yes |
| Code execution | No | No |
Benchmarks
| Benchmark | Gemini 1.5 Flash | Llama 3.1 8B Instruct |
|---|---|---|
| MMLU PRO | 59.1 | 44.3 |
Deep dive
On shared benchmark coverage, MMLU PRO has Gemini 1.5 Flash at 59.1 and Llama 3.1 8B Instruct at 44.3, with Gemini 1.5 Flash ahead by 14.9 points. The largest visible gap is 14.9 points on MMLU PRO, which matters most when that benchmark mirrors your workload. Treat isolated benchmark wins as directional, because provider routing, prompt style, and tool access can move real application results.
The capability footprint is close: both models cover structured outputs. That makes context budget, benchmark fit, and provider maturity more important than a simple checklist. If your application depends on one integration detail, verify it against the provider route you plan to use, not just the base model listing.
For cost, Gemini 1.5 Flash lists $0.07/1M input and $0.3/1M output tokens, while Llama 3.1 8B Instruct lists $0.02/1M input and $0.05/1M output tokens on the cheapest tracked provider. A 70/30 input-output blend puts Llama 3.1 8B Instruct lower by about $0.11 per million blended tokens. Availability is 2 providers versus 12, so concentration risk also matters.
Choose Gemini 1.5 Flash when long-context analysis and larger context windows are central to the workload. Choose Llama 3.1 8B Instruct when provider fit, lower input-token cost, and broader provider choice are more important. For production, rerun your own prompts through the exact provider, region, and tool stack you plan to ship.
FAQ
Which has a larger context window, Gemini 1.5 Flash or Llama 3.1 8B Instruct?
Gemini 1.5 Flash supports 1M tokens, while Llama 3.1 8B Instruct supports 128K tokens. That gap matters most for long documents, large codebases, retrieval-heavy agents, and conversations where earlier context must remain visible.
Which is cheaper, Gemini 1.5 Flash or Llama 3.1 8B Instruct?
Llama 3.1 8B Instruct is cheaper on tracked token pricing. Gemini 1.5 Flash costs $0.07/1M input and $0.3/1M output tokens. Llama 3.1 8B Instruct costs $0.02/1M input and $0.05/1M output tokens. Provider discounts or batch pricing can still change the final bill.
Is Gemini 1.5 Flash or Llama 3.1 8B Instruct open source?
Gemini 1.5 Flash is listed under Unknown. Llama 3.1 8B Instruct is listed under Open Source. License labels affect whether you can self-host, redistribute weights, or rely only on hosted APIs, so confirm the upstream license before deployment.
Which is better for structured outputs, Gemini 1.5 Flash or Llama 3.1 8B Instruct?
Both Gemini 1.5 Flash and Llama 3.1 8B Instruct expose structured outputs. The better choice depends on benchmark fit, context budget, pricing, and whether your provider route exposes the same capability surface.
Where can I run Gemini 1.5 Flash and Llama 3.1 8B Instruct?
Gemini 1.5 Flash is available on GCP Vertex AI and Google AI Studio. Llama 3.1 8B Instruct is available on OctoAI API (Deprecated), Together AI, Fireworks AI, NVIDIA NIM, and GroqCloud. Provider coverage can affect latency, region availability, compliance posture, and fallback options.
When should I pick Gemini 1.5 Flash over Llama 3.1 8B Instruct?
Llama 3.1 8B Instruct is ~275% cheaper at $0.02/1M; pay for Gemini 1.5 Flash only for long-context analysis. If your workload also depends on long-context analysis, start with Gemini 1.5 Flash; if it depends on provider fit, run the same evaluation with Llama 3.1 8B Instruct.
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Last reviewed: 2026-05-16. Data sourced from public model cards and provider documentation.