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LLM Context Window Comparison

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See how much text each model can take in one request. The chart compares context windows (or max output) across OpenAI, Anthropic, Google, Mistral, Meta, DeepSeek and xAI, and the fit check shows which models can hold your prompt.

e.g. 150k — models that can't hold it turn red
  • GPT-5.6 Sol
    OpenAI
    1.05M922K max in
  • GPT-5.6 Terra
    OpenAI
    1.05M922K max in
  • GPT-6 Astra
    OpenAI
    1.05M
  • GPT-6 Luna
    OpenAI
    1.05M
  • GPT-6 Sol
    OpenAI
    1.05M922K max in
  • GPT-6.1 Sol
    OpenAI
    1.05M
  • Gemini 2.5 Pro
    Google
    1M
  • Gemini 3.1 Flash-Lite
    Google
    1M
  • Gemini 3.1 Pro (preview)
    Google
    1M
  • Gemini 3.5 Flash-Lite
    Google
    1M
  • Gemini 3.8 Flash
    Google
    1M
  • Gemini 4 Argon
    Google
    1M
  • Claude Fable 5.1
    Anthropic
    1M
  • Claude Opus 4.8
    Anthropic
    1M
  • Claude Opus 5
    Anthropic
    1M
  • Claude Opus 5.5
    Anthropic
    1M
  • Claude Sonnet 5
    Anthropic
    1M
  • Claude Sonnet 5.5
    Anthropic
    1M
  • DeepSeek Flash
    DeepSeek
    1M
  • DeepSeek V4 Pro
    DeepSeek
    1M
  • Grok 4.3
    xAI
    1M
  • Mistral Large 4
    Mistral
    1M
  • Grok 4.7
    xAI
    500K
  • Grok Build 0.1
    xAI
    256K
  • Ministral 3 8B
    Mistral
    256K
  • Mistral Medium 3.5
    Mistral
    256K
  • Mistral Small 4
    Mistral
    256K
  • Llama 3.3 70B
    Meta (Llama) · Together AI
    128K
  • Codestral
    Mistral
    128K

Prices checked on 2026-10-18 from each provider's official pricing page (standard tier, USD per 1M tokens). Prices change often — verify before you budget.

How to compare context windows

  1. Pick providers, and switch between context window and maximum output tokens.
  2. Type your prompt size (e.g. 150k) to see which models can hold it — models that can't turn red.
  3. Check the full table below for exact limits, including separate maximum-input caps.

What a context window is

The context window is the maximum number of tokens a model can consider in one request: your system prompt, the conversation history, any documents or tool results, and the response it generates. If input plus output exceeds it, the request fails or old messages must be dropped. Some models also cap input separately — GPT-5 has a 400K window but accepts at most 272K input tokens.

All context windows

ModelContext windowMax output≈ English words
GPT-5.4 (OpenAI)1,050,000128,000788K
GPT-5.5 (OpenAI)1,050,000128,000788K
GPT-5.6 Luna (OpenAI)1,050,000
max input 922,000
128,000788K
GPT-5.6 Sol (OpenAI)1,050,000
max input 922,000
128,000788K
GPT-5.6 Terra (OpenAI)1,050,000
max input 922,000
128,000788K
GPT-6 Astra (OpenAI)1,050,000128,000788K
GPT-6 Luna (OpenAI)1,050,000128,000788K
GPT-6 Sol (OpenAI)1,050,000
max input 922,000
128,000788K
GPT-6.1 Sol (OpenAI)1,050,000128,000788K
Gemini 2.5 Flash (Google)1,048,57665,536786K
Gemini 2.5 Flash-Lite (Google)1,048,57665,536786K
Gemini 2.5 Pro (Google)1,048,57665,536786K
Gemini 3.1 Flash-Lite (Google)1,048,57665,536786K
Gemini 3.1 Pro (preview) (Google)1,048,57665,536786K
Gemini 3.5 Flash-Lite (Google)1,048,57665,536786K
Gemini 3.8 Flash (Google)1,048,57665,536786K
Gemini 4 Argon (Google)1,048,57665,536786K
GPT-4.1 (OpenAI)1,047,57632,768786K
GPT-4.1 mini (OpenAI)1,047,57632,768786K
Claude Fable 5.1 (Anthropic)1,000,000128,000750K
Claude Haiku 5.5 (Anthropic)1,000,000128,000750K
Claude Opus 4.8 (Anthropic)1,000,000128,000750K
Claude Opus 5 (Anthropic)1,000,000128,000750K
Claude Opus 5.5 (Anthropic)1,000,000128,000750K
Claude Sonnet 4.6 (Anthropic)1,000,000128,000750K
Claude Sonnet 5 (Anthropic)1,000,000128,000750K
Claude Sonnet 5.5 (Anthropic)1,000,000128,000750K
DeepSeek Flash (DeepSeek)1,000,000384,000750K
DeepSeek V4 Pro (DeepSeek)1,000,000384,000750K
Grok 4.3 (xAI)1,000,000—750K
Mistral Large 4 (Mistral)1,000,000—750K
Grok 4.7 (xAI)500,000—375K
GPT-5 (OpenAI)400,000
max input 272,000
128,000300K
GPT-5 mini (OpenAI)400,000
max input 272,000
128,000300K
GPT-5 nano (OpenAI)400,000
max input 272,000
128,000300K
GPT-5.4 mini (OpenAI)400,000
max input 272,000
128,000300K
GPT-5.4 nano (OpenAI)400,000
max input 272,000
128,000300K
Grok Build 0.1 (xAI)256,000—192K
Ministral 3 8B (Mistral)256,000—192K
Mistral Medium 3.5 (Mistral)256,000—192K
Mistral Small 4 (Mistral)256,000—192K
Claude Haiku 4.5 (Anthropic)200,00064,000150K
o3 (OpenAI)200,000100,000150K
o4-mini (OpenAI)200,000100,000150K
gpt-oss-120b (OpenAI · Groq)131,07265,53698K
gpt-oss-20b (OpenAI · Groq)131,07265,53698K
Llama 3.3 70B (Meta (Llama) · Together AI)131,072—98K
Codestral (Mistral)128,000—96K
GPT-4o (OpenAI)128,00016,38496K
GPT-4o mini (OpenAI)128,00016,38496K

Bigger isn't automatically better

  • Cost scales with what you send. A full 1M-token prompt on GPT-6 Sol costs $4.00 per call — and long-context surcharges kick in above 272K on OpenAI and 200K on Gemini Pro and Grok.
  • Recall drops in the middle. Models retrieve facts near the start and end of long prompts more reliably; put key instructions last.
  • Latency grows with prompt length. Retrieval (RAG) that sends only relevant chunks is often faster and cheaper than stuffing everything in.

Context sizes in tokens: 1M tokens ≈ 750,000 English words ≈ 1,500 pages. Count your own text with the token counter.

Related tools

Frequently asked questions

Which LLM has the largest context window?

Several current models accept about 1M tokens: GPT-6 and GPT-5.4+ (1.05M), Claude Fable, Opus, Sonnet and Haiku 5.5 (1M), Gemini (1,048,576), Mistral Large 4, Grok 4.3 and DeepSeek V4 (1M).

Do output tokens count toward the context window?

Yes. Input and output share the window, so a 128K model given 120K tokens of input can only reply with about 8K tokens.

How many pages fit in 200K tokens?

About 150,000 English words, or roughly 300 pages at 500 words per page. Code and non-English text fit less.

Are these limits up to date?

Limits were checked on 2026-10-18 from each provider's model documentation. Providers raise limits often, so verify for your account and API tier.

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