LLM Reference

GPT-4 Turbo (older v1106) vs GPT-5.5

GPT-4 Turbo (older v1106) (2023) and GPT-5.5 (2026) are frontier reasoning models from OpenAI. GPT-4 Turbo (older v1106) ships a 128k-token context window, while GPT-5.5 ships a 1.05m-token context window. On pricing, GPT-4 Turbo (older v1106) costs $10/1M input tokens; GPT-5.5 ranges from $5 to $10/1M input tokens by tier. 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 GPT-4 Turbo (older v1106) for tighter calls.

Decision scorecard

Local evidence first
SignalGPT-4 Turbo (older v1106)GPT-5.5
Best forgeneral production evaluationreasoning-heavy apps, multimodal apps, and tool-calling agents
Decision fitRAG, Long context, and ClassificationCoding, RAG, and Agents
Context window128k1.05m
Cheapest output$30/1M tokens$30/1M tokens
Provider routes1 tracked3 tracked
Shared benchmarks0 rows0 rows

Decision tradeoffs

Choose GPT-4 Turbo (older v1106) when...
  • Local decision data tags GPT-4 Turbo (older v1106) for RAG, Long context, and Classification.
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 procurement flexibility.
  • GPT-5.5 uniquely exposes Vision, Multimodal, and Reasoning in local model data.
  • Local decision data tags GPT-5.5 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-5.5

GPT-4 Turbo (older v1106)

$15,500

Cheapest tracked route/tier: OpenRouter

GPT-5.5

$11,500

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

Estimated monthly gap: $4,000. Batch, cache, alternate speed tiers, and negotiated pricing are excluded from this local estimate.

Switch friction

GPT-4 Turbo (older v1106) -> GPT-5.5
  • Provider overlap exists on OpenRouter; start route-level A/B tests there.
  • Cheapest tracked output pricing is tied, so migration risk shifts to quality, latency, and provider packaging.
  • GPT-5.5 adds Vision, Multimodal, and Reasoning in local capability data.
GPT-5.5 -> GPT-4 Turbo (older v1106)
  • Provider overlap exists on OpenRouter; start route-level A/B tests there.
  • Cheapest tracked output pricing is tied, so migration risk shifts to quality, latency, and provider packaging.
  • Check replacement coverage for Vision, Multimodal, and Reasoning before moving production traffic.

Specs

Specification
Released2023-11-062026-04-23
Context window128k1.05m
Parameters
Architecturedecoder onlydecoder only
LicenseUnknownProprietary
Knowledge cutoff2023-042025-12

Pricing and availability

Pricing attributeGPT-4 Turbo (older v1106)GPT-5.5
Input price$10/1M tokens
0-272K input tokens
$5/1M tokens
Standard GPT-5.5 token pricing before the long-context surcharge threshold.
0-272,000t
$5/1M tokens
272K+ input tokens
$8/1M tokens
Long-context surcharge applies above 272K input tokens for the full session.
272,000t+
$10/1M tokens
Output price$30/1M tokens
0-272K input tokens
$30/1M tokens
Standard GPT-5.5 token pricing before the long-context surcharge threshold.
0-272,000t
$30/1M tokens
272K+ input tokens
$36/1M tokens
Long-context surcharge applies above 272K input tokens for the full session.
272,000t+
$45/1M tokens
Providers

Capabilities

CapabilityGPT-4 Turbo (older v1106)GPT-5.5
VisionNoYes
MultimodalNoYes
ReasoningNoYes
Function callingNoYes
Tool useNoYes
Structured outputsYesYes
Code executionNoYes
IDE integrationNoNo
Computer useNoNo
Parallel agentsNoNo

Benchmarks

No shared benchmark rows are currently sourced for this pair.

Deep dive

The capability footprint differs most on vision: GPT-5.5, multimodal input: GPT-5.5, reasoning mode: GPT-5.5, function calling: GPT-5.5, tool use: GPT-5.5, and code execution: GPT-5.5. Both models share structured outputs, 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, GPT-4 Turbo (older v1106) lists $10/1M input and $30/1M output tokens on the cheapest tracked provider, while GPT-5.5 lists tiered pricing: 0-272K input tokens is $5/1M input and $30/1M output; 0-272,000t is $5/1M input and $30/1M output; 272K+ input tokens is $8/1M input and $36/1M output; 272,000t+ is $10/1M input and $45/1M output. A 70/30 input-output blend puts GPT-5.5 lower by about $3.50 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 1 providers versus 3, so concentration risk also matters.

Choose GPT-4 Turbo (older v1106) when provider fit are central to the workload. Choose GPT-5.5 when coding workflow support, larger context windows, and lower cheapest-tier 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, GPT-4 Turbo (older v1106) or GPT-5.5?

GPT-5.5 supports 1.05m tokens, while GPT-4 Turbo (older v1106) 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, GPT-4 Turbo (older v1106) or GPT-5.5?

GPT-4 Turbo (older v1106) lists $10/1M input and $30/1M output tokens on the cheapest tracked provider. GPT-5.5 lists tiered pricing: 0-272K input tokens is $5/1M input and $30/1M output; 0-272,000t is $5/1M input and $30/1M output; 272K+ input tokens is $8/1M input and $36/1M output; 272,000t+ is $10/1M input and $45/1M output. 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 GPT-4 Turbo (older v1106) or GPT-5.5 open source?

GPT-4 Turbo (older v1106) is listed under Unknown. GPT-5.5 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, GPT-4 Turbo (older v1106) or GPT-5.5?

GPT-5.5 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. Use this as a quick comparison signal, then confirm the provider-specific limits before committing to production.

Which is better for multimodal input, GPT-4 Turbo (older v1106) or GPT-5.5?

GPT-5.5 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 GPT-4 Turbo (older v1106) and GPT-5.5?

GPT-4 Turbo (older v1106) is available on OpenRouter. GPT-5.5 is available on OpenAI API, OpenRouter, and Vercel AI Gateway. Provider coverage can affect latency, region availability, compliance posture, and fallback options.

Continue comparing

Last reviewed: 2026-06-03. Data sourced from public model cards and provider documentation.