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  • LLM comparison table
  • GPT (OpenAI)
  • Claude (Anthropic)
  • Gemini (Google)
  • Mistral (Mistral AI)
  • Llama (Meta)
  • DeepSeek
  • Qwen (Alibaba)
  • Open vs closed models
  • Which LLM to choose

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Comparison chart of the best large language models in 2026 - GPT-4o, Claude, Gemini, Mistral, Llama and DeepSeek compared

Behind the Models

The Best Large Language Models (LLMs), Compared

Guillaume Rostand, Tanguy Wincker, Adam Hruska·June 25, 2026·10 min read

As of June 2026 there is no single best LLM. For frontier reasoning and agentic coding, OpenAI's GPT-5.5 and Anthropic's Claude Opus 4.8 trade the top spot, while Google's Gemini 3.1 Pro leads on long-context multimodal work. Among open-weight models, DeepSeek V4 and Alibaba's Qwen rival closed frontier models at a fraction of the cost, with Mistral the leading European option. Pick Claude or GPT for coding and reasoning, Gemini for multimodal and huge context, and DeepSeek, Qwen or Mistral when you need open weights, self-hosting or low cost. Benchmarks shift monthly, so treat any ranking as a snapshot.

The best large language models in 2026 come from a tight group of labs: OpenAI (GPT), Anthropic (Claude), Google DeepMind (Gemini), Mistral AI (Mistral), Meta (Llama), DeepSeek and Alibaba (Qwen). The frontier moves fast, and no single model wins every task.

This page compares the leading LLMs by what actually matters for builders — reasoning, context window, multimodality, open versus closed weights and cost — and links each lab through to its profile in the wider AI ecosystem. It is part of our generative AI cluster.

On this page

  • Comparison table
  • GPT (OpenAI)
  • Claude (Anthropic)
  • Gemini (Google)
  • Mistral
  • Llama (Meta)
  • DeepSeek
  • Qwen (Alibaba)
  • Open vs closed
  • Which to choose

Methodology

Methodology: how we compared

"Best" depends on the job. Rather than crown one winner, we compare the leading large language models across five criteria that decide real-world fit. All figures are publisher-stated or drawn from independent leaderboards and are marked as of June 2026; the field moves fast and rankings change between updates.

  • Reasoning & coding — performance on hard, multi-step tasks and agentic benchmarks such as SWE-bench Verified and Terminal-Bench, plus general knowledge tests like MMLU-Pro and GPQA.
  • Context window — how much text, code or data the model can hold in a single request. A 1-million-token window is now common at the frontier.
  • Multimodality — whether the model natively handles images, audio, video and documents, not just text.
  • Open-weight vs closed — whether weights can be downloaded and self-hosted (open-weight) or are accessible by API only (closed). This affects cost, privacy, control and compliance.
  • Cost — API price per million tokens, and whether self-hosting is realistic on available hardware.

We cross-checked claims against the labs' own model cards, independent leaderboards including LMArena and the aggregated LLM-Stats index, and the Stanford HAI AI Index. Where a model is unreleased or specs are provisional, we say so. We do not invent benchmark numbers.

1.7%

Gap between the best closed and best open-weight model on Chatbot Arena by early 2025, down from ~8% a year earlier.

Stanford HAI, AI Index 2025

1M+

Token context window now standard at the frontier (GPT-5.5, Claude Opus 4.8, Gemini 3.1 Pro, DeepSeek V4).

OpenAI, Anthropic, Google, DeepSeek (2026)

~30x

Cheaper output tokens for the best open-weight models (DeepSeek V4) versus top closed frontier models.

DeepSeek / LLM-Stats, 2026

LLM comparison table

The table below summarises the leading models as of June 2026. Context windows are publisher-stated maximums; "open" means downloadable open-weight licences, "closed" means API-only. Specifications evolve quickly — treat this as a snapshot.

ModelCompanyTypeContext windowStrengths
GPT-5.5OpenAIClosed~1M tokensAgentic coding, tool use, broad ecosystem
Claude Opus 4.8AnthropicClosed~1M tokensReasoning, long-horizon coding, safety
Claude Sonnet 4.6AnthropicClosed1M tokens (beta)Fast, high-volume agents, cost balance
Gemini 3.1 ProGoogle DeepMindClosed1M tokensMultimodal, long context, Google stack
Mistral Large 3Mistral AIOpen (Apache 2.0)Large (MoE)Leading European open-weight model
Mistral Medium 3.5Mistral AIOpen weightsMid-largeSelf-hostable on ~4 GPUs, balanced
Llama 4 MaverickMetaOpen weights~1M tokensNatively multimodal MoE, ecosystem
Llama 4 ScoutMetaOpen weightsUp to ~10M tokensIndustry-leading context length
DeepSeek V4DeepSeekOpen (MIT)1M tokensFrontier-class at very low cost
Qwen3.6 / 3.7AlibabaMixed (open + API)256K–1M tokensStrong coding, efficient dense models

GPT (OpenAI)

OpenAI's GPT family remains the default reference point for the category and the most widely integrated through ChatGPT and the API. The current flagship, GPT-5.5, shipped in the API in April 2026 as OpenAI's first model with a 1-million-token context window, priced at $5 per million input tokens and $30 per million output tokens.

  • Strengths: agentic coding, tool use, web research, document and spreadsheet generation, and the broadest third-party ecosystem of any LLM.
  • Type: closed (API and ChatGPT only); no downloadable weights.
  • Note: OpenAI signalled a near-term successor (a GPT-5.6-class release) around mid-2026; specifications circulating before official release notes should be treated as provisional.

For most teams, GPT is the safe baseline for AI agents and coding assistants, with the deepest tooling and integrations.

Claude (Anthropic)

Anthropic's Claude is the model most often preferred for reasoning, long-horizon coding and writing. The flagship Claude Opus 4.8 (released May 2026) is the top Opus-tier model for complex reasoning and high-autonomy agentic work, with a 1-million-token context window and pricing around $5 input / $25 output per million tokens. Claude Sonnet 4.6 is the faster, cheaper hybrid-reasoning model for real-time agents and high-volume workloads, with a 1M-token window in beta.

  • Strengths: rigorous multi-step reasoning, sustained agentic coding, careful writing, and a strong safety and alignment posture.
  • Type: closed; available via the Claude API and major clouds (AWS Bedrock, Google Cloud, Microsoft Foundry).
  • Benchmarks: Claude variants have repeatedly held top positions on LMArena and reasoning benchmarks such as GPQA in 2026, though the gap with GPT and Gemini is small and shifts often.

Gemini (Google)

Google DeepMind's Gemini leads on native multimodality and long context. As of early 2026, Gemini 3.1 Pro is Google's most advanced Pro-tier reasoning model, natively handling text, audio, images, video, PDFs and entire code repositories within a 1-million-token context window. Faster Flash-tier models (Gemini 3.5 Flash and later) target high-throughput agentic and coding work at lower cost.

  • Strengths: multimodal understanding, very long context, and deep integration across Google Workspace, Android and Google Cloud.
  • Type: closed; API plus consumer Gemini apps and Google AI subscriptions.
  • Best for: teams already on the Google stack, and workloads mixing documents, images and video in one prompt.

Mistral (Mistral AI)

Mistral AI, founded in Paris in 2023, is Europe's leading LLM lab and the strongest open-weight option from the continent. Mistral Large 3 (December 2025) is described as the largest open-weight Mixture-of-Experts model from a major lab, around 675B total parameters with 41B active, released under Apache 2.0. Mistral Medium 3.5 (March 2026) merges instruction-following, reasoning and coding into a single 128B dense model that self-hosts on as few as four GPUs, while Mistral Small 4 folds reasoning, vision and agentic coding into one compact model.

  • Strengths: open weights, European data residency and sovereignty, efficient self-hosting, and a fast release cadence across sizes.
  • Type: mostly open-weight (Apache 2.0 / permissive licences), plus an API platform.
  • Why it matters: for European enterprises with AI Act and sovereignty concerns, Mistral is the natural open-weight default. Hugging Face's Nouamane Tazi and others in the open-source community work closely with models like these.

Llama (Meta)

Meta's Llama 4 family (launched April 2025) was Meta's first natively multimodal, Mixture-of-Experts open-weight line. Llama 4 Scout offers an industry-leading context window of up to ~10 million tokens (109B total / 17B active). Llama 4 Maverick (~400B total / 17B active, 128 experts) targets best-in-class multimodal performance with a ~1M-token window. The largest model, Llama 4 Behemoth, was previewed as still in training; as of mid-2026 public weights had not shipped.

  • Strengths: very long context, native multimodality, and the largest open-weight developer ecosystem.
  • Type: open weights under Meta's community licence (with some usage restrictions, so not as permissive as Apache 2.0 or MIT).
  • Best for: teams wanting a widely supported open-weight base with massive context and broad tooling.

DeepSeek

China's DeepSeek reset open-weight economics. DeepSeek V4 (April 2026) is an MIT-licensed Mixture-of-Experts family in two variants: V4-Pro (1.6T total / 49B active) and V4-Flash (284B total / 13B active), both with a 1-million-token context window. Independent reports put V4-Pro at the top of open-weight SWE-bench Verified scores and competitive with top closed models on agentic benchmarks, at roughly 10–30x lower cost per output token.

  • Strengths: frontier-class reasoning and coding at dramatically lower cost; fully open weights under a permissive licence.
  • Type: open-weight (MIT), with a low-cost API.
  • Caveat: some enterprises and regulators scrutinise China-origin models for governance and data-handling; evaluate against your enterprise AI and compliance requirements.

Qwen (Alibaba)

Alibaba's Qwen family is among the most capable open-weight lines and a benchmark favourite for coding. Qwen3.6-27B (April 2026) is a dense, Apache-2.0 open-weight model that reportedly matches or beats far larger MoE models on agentic coding benchmarks, with a native 256K context extendable toward 1M via scaling. Alibaba has also moved its top-tier Qwen3.7 Max (May 2026) to a closed, API-only release with a full 1M-token context, a notable shift after years of fully open flagships.

  • Strengths: strong coding and reasoning per parameter, efficient dense models, and many open-weight sizes.
  • Type: mixed — most Qwen models are Apache 2.0 open-weight, but the newest flagship is API-only.
  • Best for: teams wanting capable, self-hostable models, especially for coding agents and multilingual work.

Open vs closed models

The single most important choice is open-weight versus closed. Closed models (GPT, Claude, Gemini) are API-only: you get frontier quality and managed infrastructure, but you cannot self-host or inspect the weights. Open-weight models (Mistral, Llama, DeepSeek, most Qwen) can be downloaded, fine-tuned and run on your own hardware, giving control over privacy, cost and compliance, at the price of running the infrastructure yourself.

The capability gap has narrowed sharply. The Stanford HAI AI Index 2025 found the difference between the best closed and best open-weight model on Chatbot Arena fell from about 8% to 1.7% in a single year. In 2026, DeepSeek V4 and Qwen pushed open weights to genuine frontier parity on several benchmarks, while OpenAI, Anthropic and Google retained an edge on the hardest reasoning and agentic tasks.

  • Choose closed for the absolute frontier, managed scale, and the deepest tooling, with the least operational overhead.
  • Choose open-weight for data residency, on-prem deployment, fine-tuning, lower marginal cost, and sovereignty, central for many European enterprise AI programmes.

Which LLM to choose

Map the model to the job, not to the leaderboard. As of June 2026:

  • Best for coding: Claude Opus 4.8 and GPT-5.5 lead on agentic coding; DeepSeek V4 and Qwen are the strongest open-weight coders at far lower cost.
  • Best for reasoning: Claude Opus 4.8 and GPT-5.5, with Gemini 3.1 Pro close behind.
  • Best for multimodal and long context: Gemini 3.1 Pro; Llama 4 Scout for extreme context length.
  • Best open-source LLM: DeepSeek V4 for raw capability per dollar; Mistral for European sovereignty; Llama 4 for ecosystem breadth.
  • Best for enterprise: depends on compliance, GPT or Claude for managed frontier; Mistral or Llama for self-hosted, sovereign deployments. See our enterprise AI guide.

Most serious teams now run a multi-model stack, routing each task to the best-fit model and re-evaluating quarterly as new versions ship. These are exactly the trade-offs debated by builders and researchers at AI Summit Europe.

The LLM frontier in 2026 is a fast-moving race between a handful of labs: OpenAI, Anthropic and Google at the closed frontier, Mistral, Meta, DeepSeek and Alibaba closing the gap with open weights. There is no permanent winner, only the best model for your task this month. The one constant is the pace of change, which is exactly why the European AI community keeps gathering, increasingly in Barcelona.

See the people building these models

The labs behind GPT, Claude, Gemini, Mistral, Llama, DeepSeek and Qwen, and the researchers and founders shaping them, gather at AI Summit Barcelona 2026. From foundation models to AI agents and enterprise deployment, it is where the next generation of LLMs is debated up close.

Get your tickets →

If this interests you

  • The labs: OpenAI, Anthropic, Google DeepMind, Mistral AI and Meta AI.
  • The topics: Large Language Models, Generative AI and AI Agents.
  • Go deeper: the AI Summit Europe dossier and our Enterprise AI Guide.
  • Plan who to meet: browse the speakers — including Nouamane Tazi — and get your tickets.

Sources

  • Official model cards and announcements from OpenAI, Anthropic, Google DeepMind, Mistral AI, Meta, DeepSeek and Alibaba (Qwen)
  • Independent leaderboards: LMArena and the aggregated LLM-Stats index
  • Stanford HAI — AI Index 2025 for open-vs-closed and capability trends

Frequently asked questions

Which is the best LLM in 2026?+

There is no single best LLM. As of June 2026, GPT-5.5 (OpenAI) and Claude Opus 4.8 (Anthropic) lead on reasoning and agentic coding, Gemini 3.1 Pro (Google) leads on multimodal and long context, and DeepSeek V4 and Qwen lead among open-weight models. The best choice depends on your task, budget and whether you need open weights. Rankings shift monthly.

Is Claude better than GPT?+

It depends on the task. Claude Opus 4.8 is often preferred for rigorous reasoning, long-horizon agentic coding and careful writing, while GPT-5.5 has the broadest ecosystem and very strong agentic tool use. Both sit at the frontier with a small, frequently changing gap. Many teams use both and route tasks to whichever performs better.

What is the best open-source LLM?+

Most open frontier models are open-weight rather than fully open-source. As of June 2026, DeepSeek V4 (MIT) offers frontier-class capability at very low cost, Mistral Large 3 (Apache 2.0) is the leading European open-weight model, Alibaba's Qwen is a top open-weight coder, and Llama 4 (Meta) has the largest ecosystem and extreme context length.

What is the best LLM for coding?+

For agentic coding, Claude Opus 4.8 and GPT-5.5 are the strongest closed models, scoring highly on benchmarks like SWE-bench Verified and Terminal-Bench. Among open-weight options, DeepSeek V4 and Qwen are very competitive at a fraction of the cost, making them popular for self-hosted coding agents.

What is the best LLM for enterprise?+

For managed, frontier-quality enterprise use, GPT-5.5 or Claude via API and major clouds are common defaults. For data residency, on-prem deployment and AI Act sovereignty, European enterprises often prefer open-weight Mistral or Llama 4. The right answer depends on compliance, latency and cost.

What is a context window and why does it matter?+

A context window is how much text, code or data a model can process in a single request, measured in tokens. Larger windows let a model reason over whole codebases, long documents or many files at once. In 2026, a 1-million-token window is standard at the frontier (GPT-5.5, Claude Opus 4.8, Gemini 3.1 Pro, DeepSeek V4), and Llama 4 Scout reaches up to about 10 million tokens.

Reviewed by the AI Summit Barcelona editorial team: Guillaume Rostand, Tanguy Wincker, Adam Hruska.

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