LLM Reference

GPT-5.5 vs Grok 3 Mini

GPT-5.5 (2026) and Grok 3 Mini (2025) are frontier reasoning models from OpenAI and xAI. GPT-5.5 ships a 1.05m-token context window, while Grok 3 Mini ships a 131k-token context window. On pricing, GPT-5.5 ranges from $5 to $8/1M input tokens by tier; Grok 3 Mini costs $0.25/1M input tokens. This comparison covers specs, pricing, API access, capabilities, benchmarks, input and output token costs, and production fit for coding and agent workloads.

GPT-5.5 fits 8x more tokens; pick it for long-context work and Grok 3 Mini for tighter calls.

Decision scorecard

Local evidence first
SignalGPT-5.5Grok 3 Mini
Best forreasoning-heavy apps, multimodal apps, and tool-calling agentsmultimodal apps and provider-routed production
Decision fitCoding, RAG, and AgentsRAG, Long context, and Vision
Context window1.05m131k
Cheapest output$30/1M tokens$1.27/1M tokens
Provider routes4 tracked2 tracked
Shared benchmarks0 shared0 shared

Decision tradeoffs

Choose GPT-5.5 when...
  • GPT-5.5 has the larger context window for long prompts, retrieval packs, or transcript analysis.
  • GPT-5.5 has broader tracked provider coverage for fallback and route flexibility.
  • GPT-5.5 uniquely exposes Reasoning, JSON / Tool use, and Code execution in local model data.
  • Local decision data tags GPT-5.5 for Coding, RAG, and Agents.
Choose Grok 3 Mini when...
  • Grok 3 Mini has the lower cheapest tracked output price at $1.27/1M tokens.
  • Local decision data tags Grok 3 Mini for RAG, Long context, and Vision.

Monthly cost at traffic

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

Lower estimate Grok 3 Mini

GPT-5.5

$11,500

Cheapest tracked route/tier: OpenAI API 0-272K input tokens

Grok 3 Mini

$518

Cheapest tracked route/tier: Microsoft Foundry

Estimated monthly gap: $10,983. Batch, cache, alternate speed tiers, and negotiated pricing are excluded from this local estimate.

Switch friction

GPT-5.5 -> Grok 3 Mini
  • Provider overlap exists on OpenRouter; start route-level A/B tests there.
  • Grok 3 Mini is $28.73/1M tokens lower on cheapest tracked output pricing before cache, batch, or negotiated discounts.
  • Check replacement coverage for Reasoning, JSON / Tool use, and Code execution before moving production traffic.
Grok 3 Mini -> GPT-5.5
  • Provider overlap exists on OpenRouter; start route-level A/B tests there.
  • GPT-5.5 is $28.73/1M tokens higher on cheapest tracked output pricing, so quality gains need to justify the spend.
  • GPT-5.5 adds Reasoning, JSON / Tool use, and Code execution in local capability data.

Specs

Specification
Released2026-04-232025-02-17
Context window1.05m131k
Parameters
ArchitectureDecoder Only-
LicenseProprietaryProprietary
OpennessProprietaryProprietary
WeightsNot releasedNot released
CodeUnknownUnknown
Commercial useCommercial use: conditionalCommercial use: conditional
Knowledge cutoff2025-122024-11

Pricing and availability

Pricing attributeGPT-5.5Grok 3 Mini
Input price
0-272K input tokens
$5/1M tokens
Standard GPT-5.5 token pricing before the long-context surcharge threshold.
272K+ input tokens
$8/1M tokens
Long-context surcharge applies above 272K input tokens for the full session.
$0.25/1M tokens
Output price
0-272K input tokens
$30/1M tokens
Standard GPT-5.5 token pricing before the long-context surcharge threshold.
272K+ input tokens
$36/1M tokens
Long-context surcharge applies above 272K input tokens for the full session.
$1.27/1M tokens
Providers

Capabilities

CapabilityGPT-5.5Grok 3 Mini
VisionYesYes
MultimodalYesYes
ReasoningYesNo
JSON / Tool useYesNo
Structured outputsYesYes
Code executionYesNo
IDE integrationNoNo
Computer useNoNo
Parallel agentsNoNo

Benchmarks

No shared benchmark scores are currently available for this pair.

Continue comparing

Last reviewed: 2026-06-29. Data sourced from public model cards and provider documentation.