LLM Reference

Claude Sonnet 4.5 vs GPT-4.1

Claude Sonnet 4.5 (2025) and GPT-4.1 (2025) are frontier reasoning models from Anthropic and OpenAI. Claude Sonnet 4.5 ships a 200K-token context window, while GPT-4.1 ships a 1M-token context window. On MMLU PRO, Claude Sonnet 4.5 leads by 4.2 pts. On pricing, Claude Sonnet 4.5 ranges from $3 to $6/1M input tokens by tier; GPT-4.1 costs $2/1M input tokens. This comparison covers specs, pricing, capabilities, benchmarks, provider availability, and production fit.

GPT-4.1 fits 5x more tokens; pick it for long-context work and Claude Sonnet 4.5 for tighter calls.

Decision scorecard

Local evidence first
SignalClaude Sonnet 4.5GPT-4.1
Best forreasoning-heavy apps, multimodal apps, and tool-calling agentsmultimodal apps, tool-calling agents, and long-context analysis
Decision fitCoding, RAG, and AgentsCoding, RAG, and Agents
Context window200K1M
Cheapest output$15/1M tokens$8/1M tokens
Provider routes8 tracked4 tracked
Shared benchmarksMMLU PRO leader3 rows

Decision tradeoffs

Choose Claude Sonnet 4.5 when...
  • Claude Sonnet 4.5 leads the largest shared benchmark signal on MMLU PRO by 4.2 points.
  • Claude Sonnet 4.5 has broader tracked provider coverage for fallback and procurement flexibility.
  • Claude Sonnet 4.5 uniquely exposes Reasoning in local model data.
  • Local decision data tags Claude Sonnet 4.5 for Coding, RAG, and Agents.
Choose GPT-4.1 when...
  • GPT-4.1 has the larger context window for long prompts, retrieval packs, or transcript analysis.
  • GPT-4.1 has the lower cheapest tracked output price at $8/1M tokens.
  • GPT-4.1 uniquely exposes Code execution in local model data.
  • Local decision data tags GPT-4.1 for Coding, RAG, and Agents.

Monthly cost at traffic

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

Lower estimate GPT-4.1

Claude Sonnet 4.5

$6,150

Cheapest tracked route/tier: Microsoft Foundry

GPT-4.1

$3,600

Cheapest tracked route/tier: OpenRouter

Estimated monthly gap: $2,550. Batch, cache, alternate speed tiers, and negotiated pricing are excluded from this local estimate.

Switch friction

Claude Sonnet 4.5 -> GPT-4.1
  • Provider overlap exists on OpenRouter and Vercel AI Gateway; start route-level A/B tests there.
  • GPT-4.1 is $7/1M tokens lower on cheapest tracked output pricing before cache, batch, or negotiated discounts.
  • Check replacement coverage for Reasoning before moving production traffic.
  • GPT-4.1 adds Code execution in local capability data.
GPT-4.1 -> Claude Sonnet 4.5
  • Provider overlap exists on OpenRouter and Vercel AI Gateway; start route-level A/B tests there.
  • Claude Sonnet 4.5 is $7/1M tokens higher on cheapest tracked output pricing, so quality gains need to justify the spend.
  • Check replacement coverage for Code execution before moving production traffic.
  • Claude Sonnet 4.5 adds Reasoning in local capability data.

Specs

Specification
Released2025-09-292025-04-01
Context window200K1M
Parameters
Architecturedecoder onlydecoder only
LicenseProprietaryProprietary
Knowledge cutoff2025-122025-01

Pricing and availability

Pricing attributeClaude Sonnet 4.5GPT-4.1
Input price
0-200,001t
$3/1M tokens
200,001t+
$6/1M tokens
$2/1M tokens
Output price
0-200,001t
$15/1M tokens
200,001t+
$22.50/1M tokens
$8/1M tokens
Providers

Capabilities

CapabilityClaude Sonnet 4.5GPT-4.1
VisionYesYes
MultimodalYesYes
ReasoningYesNo
Function callingYesYes
Tool useYesYes
Structured outputsYesYes
Code executionNoYes
IDE integrationNoNo
Computer useNoNo
Parallel agentsNoNo

Benchmarks

BenchmarkClaude Sonnet 4.5GPT-4.1
MMLU PRO86.081.8
SWE-bench Verified77.254.6
BFCL73.254.0

Deep dive

On shared benchmark coverage, MMLU PRO has Claude Sonnet 4.5 at 86 and GPT-4.1 at 81.8, with Claude Sonnet 4.5 ahead by 4.2 points; SWE-bench Verified has Claude Sonnet 4.5 at 77.2 and GPT-4.1 at 54.6, with Claude Sonnet 4.5 ahead by 22.6 points; BFCL has Claude Sonnet 4.5 at 73.2 and GPT-4.1 at 54.0, with Claude Sonnet 4.5 ahead by 19.3 points. The largest visible gap is 22.6 points on SWE-bench Verified, 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 differs most on reasoning mode: Claude Sonnet 4.5 and code execution: GPT-4.1. Both models share vision, multimodal input, function calling, and tool use, 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, Claude Sonnet 4.5 lists tiered pricing: 0-200,001t is $3/1M input and $15/1M output; 200,001t+ is $6/1M input and $22.50/1M output, while GPT-4.1 lists $2/1M input and $8/1M output tokens on the cheapest tracked provider. A 70/30 input-output blend puts GPT-4.1 lower by about $2.80 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 8 providers versus 4, so concentration risk also matters.

Choose Claude Sonnet 4.5 when reasoning depth and broader provider choice are central to the workload. Choose GPT-4.1 when coding workflow support, larger context windows, 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, Claude Sonnet 4.5 or GPT-4.1?

GPT-4.1 supports 1M tokens, while Claude Sonnet 4.5 supports 200K tokens. That gap matters most for long documents, large codebases, retrieval-heavy agents, and conversations where earlier context must remain visible.

Which is cheaper, Claude Sonnet 4.5 or GPT-4.1?

Claude Sonnet 4.5 lists tiered pricing: 0-200,001t is $3/1M input and $15/1M output; 200,001t+ is $6/1M input and $22.50/1M output. GPT-4.1 lists $2/1M input and $8/1M 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 Claude Sonnet 4.5 or GPT-4.1 open source?

Claude Sonnet 4.5 is listed under Proprietary. GPT-4.1 is listed under Proprietary. 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, Claude Sonnet 4.5 or GPT-4.1?

Both Claude Sonnet 4.5 and GPT-4.1 expose vision. The better choice depends on benchmark fit, context budget, pricing, and whether your provider route exposes the same capability surface. Use this as a quick comparison signal, then confirm the provider-specific limits before committing to production.

Which is better for multimodal input, Claude Sonnet 4.5 or GPT-4.1?

Both Claude Sonnet 4.5 and GPT-4.1 expose multimodal input. The better choice depends on benchmark fit, context budget, pricing, and whether your provider route exposes the same capability surface. Use this as a quick comparison signal, then confirm the provider-specific limits before committing to production.

Where can I run Claude Sonnet 4.5 and GPT-4.1?

Claude Sonnet 4.5 is available on Microsoft Foundry, Anthropic, Snowflake Cortex, GCP Vertex AI, and AWS Bedrock. GPT-4.1 is available on OpenRouter, Azure OpenAI, OpenAI API, and Vercel AI Gateway. Provider coverage can affect latency, region availability, compliance posture, and fallback options.

Continue comparing

Last reviewed: 2026-05-22. Data sourced from public model cards and provider documentation.