LLM Reference

Gemini 3.1 Pro Preview vs Llama Guard 3 1B

Gemini 3.1 Pro Preview (2026) and Llama Guard 3 1B (2024) are compact production models from Google DeepMind and AI at Meta. Gemini 3.1 Pro Preview ships a 1m-token context window, while Llama Guard 3 1B ships a 128k-token context window. This comparison covers specs, pricing, API access, capabilities, benchmarks, input and output token costs, and production fit for coding and agent workloads.

Gemini 3.1 Pro Preview fits 8x more tokens; pick it for long-context work and Llama Guard 3 1B for tighter calls.

Decision scorecard

Local evidence first
SignalGemini 3.1 Pro PreviewLlama Guard 3 1B
Best formultimodal apps, tool-calling agents, and long-context analysisgeneral production evaluation
Decision fitCoding, RAG, and AgentsLong context and Classification
Context window1m128k
Cheapest output$12/1M tokens$0.10/1M tokens
Provider routes5 tracked1 tracked
Shared benchmarks0 shared0 shared

Decision tradeoffs

Choose Gemini 3.1 Pro Preview when...
  • Gemini 3.1 Pro Preview has the larger context window for long prompts, retrieval packs, or transcript analysis.
  • Gemini 3.1 Pro Preview has broader tracked provider coverage for fallback and procurement flexibility.
  • Gemini 3.1 Pro Preview uniquely exposes Vision, Multimodal, and Function calling in local model data.
  • Local decision data tags Gemini 3.1 Pro Preview for Coding, RAG, and Agents.
Choose Llama Guard 3 1B when...
  • Llama Guard 3 1B has the lower cheapest tracked output price at $0.10/1M tokens.
  • Local decision data tags Llama Guard 3 1B for Long context and Classification.

Monthly cost at traffic

Estimate token spend from the cheapest tracked input and output route or tier on this page.

Lower estimate Llama Guard 3 1B

Gemini 3.1 Pro Preview

$4,600

Cheapest tracked route/tier: Google AI Studio

Llama Guard 3 1B

$105

Cheapest tracked route/tier: Fireworks AI

Estimated monthly gap: $4,495. Batch, cache, alternate speed tiers, and negotiated pricing are excluded from this local estimate.

Switch friction

Gemini 3.1 Pro Preview -> Llama Guard 3 1B
  • No overlapping tracked provider route is sourced for Gemini 3.1 Pro Preview and Llama Guard 3 1B; plan for SDK, billing, or endpoint changes.
  • Llama Guard 3 1B is $11.90/1M tokens lower on cheapest tracked output pricing before cache, batch, or negotiated discounts.
  • Check replacement coverage for Vision, Multimodal, and Function calling before moving production traffic.
Llama Guard 3 1B -> Gemini 3.1 Pro Preview
  • No overlapping tracked provider route is sourced for Llama Guard 3 1B and Gemini 3.1 Pro Preview; plan for SDK, billing, or endpoint changes.
  • Gemini 3.1 Pro Preview is $11.90/1M tokens higher on cheapest tracked output pricing, so quality gains need to justify the spend.
  • Gemini 3.1 Pro Preview adds Vision, Multimodal, and Function calling in local capability data.

Specs

Specification
Released2026-02-192024-09-25
Context window1m128k
Parameters1B
ArchitectureDecoder OnlyDecoder Only
LicenseProprietaryLlama 2 Community
OpennessProprietaryOpen weights
Commercial useCommercial use: conditionalCommercial use: conditional
Knowledge cutoff2025-012023-12

Pricing and availability

Pricing attributeGemini 3.1 Pro PreviewLlama Guard 3 1B
Input price
0-200,001t
$2/1M tokens
200,001t+
$4/1M tokens
$0.10/1M tokens
Output price
0-200,001t
$12/1M tokens
200,001t+
$18/1M tokens
$0.10/1M tokens
Providers

Capabilities

CapabilityGemini 3.1 Pro PreviewLlama Guard 3 1B
VisionYesNo
MultimodalYesNo
ReasoningNoNo
Function callingYesNo
Tool useYesNo
Structured outputsYesNo
Code executionYesNo
IDE integrationNoNo
Computer useNoNo
Parallel agentsNoNo

Benchmarks

No shared benchmark scores are currently available for this pair.

Deep dive

The capability footprint differs most on vision: Gemini 3.1 Pro Preview, multimodal input: Gemini 3.1 Pro Preview, function calling: Gemini 3.1 Pro Preview, tool use: Gemini 3.1 Pro Preview, structured outputs: Gemini 3.1 Pro Preview, and code execution: Gemini 3.1 Pro Preview. Both models share the core language-model surface, so the practical split is not just feature count. Use those differences to decide whether the page is about raw model quality, agentic coding support, multimodal ingestion, or predictable structured API behavior.

For cost, Gemini 3.1 Pro Preview lists tiered pricing: 0-200,001t is $2/1M input and $12/1M output; 200,001t+ is $4/1M input and $18/1M output, while Llama Guard 3 1B lists $0.10/1M input and $0.10/1M output tokens on the cheapest tracked provider. A 70/30 input-output blend puts Llama Guard 3 1B lower by about $4.90 per million blended tokens. For tiered rows, this cheapest-track view can understate interactive or fast-lane spend, so compare the tier you will actually use. Availability is 5 providers versus 1, so concentration risk also matters.

Choose Gemini 3.1 Pro Preview when coding workflow support, larger context windows, and broader provider choice are central to the workload. Choose Llama Guard 3 1B when provider fit and lower input-token cost 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 3.1 Pro Preview or Llama Guard 3 1B?

Gemini 3.1 Pro Preview supports 1m tokens, while Llama Guard 3 1B 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 3.1 Pro Preview or Llama Guard 3 1B?

Gemini 3.1 Pro Preview lists tiered pricing: 0-200,001t is $2/1M input and $12/1M output; 200,001t+ is $4/1M input and $18/1M output. Llama Guard 3 1B lists $0.10/1M input and $0.10/1M output tokens on the cheapest tracked provider. Compare the tier you will actually use; cheap async pricing can overstate savings for interactive workflows. Provider discounts or batch pricing can still change the final bill.

Is Gemini 3.1 Pro Preview or Llama Guard 3 1B open source?

Gemini 3.1 Pro Preview is listed under Proprietary. Llama Guard 3 1B is listed under Llama 2 Community. 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 vision, Gemini 3.1 Pro Preview or Llama Guard 3 1B?

Gemini 3.1 Pro Preview has the clearer documented vision signal in this comparison. If vision is mission-critical, validate it against the provider endpoint because model-level support and API-level exposure can differ.

Which is better for multimodal input, Gemini 3.1 Pro Preview or Llama Guard 3 1B?

Gemini 3.1 Pro Preview has the clearer documented multimodal input signal in this comparison. If multimodal input is mission-critical, validate it against the provider endpoint because model-level support and API-level exposure can differ.

Where can I run Gemini 3.1 Pro Preview and Llama Guard 3 1B?

Gemini 3.1 Pro Preview is available on Google AI Studio, GCP Vertex AI, OpenRouter, Replicate API, and Vercel AI Gateway. Llama Guard 3 1B is available on Fireworks AI. Provider coverage can affect latency, region availability, compliance posture, and fallback options.

Continue comparing

Last reviewed: 2026-06-19. Data sourced from public model cards and provider documentation.