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The Best Open-Weight LLMs in 2026: DeepSeek, Qwen, Llama, GLM and Kimi

Open models now match or beat closed frontier ones on key benchmarks. Here is how to pick among DeepSeek, Qwen, GLM, Kimi and Llama by license and use case.

Sam Carter 8 min read
Cover image for The Best Open-Weight LLMs in 2026: DeepSeek, Qwen, Llama, GLM and Kimi
Photo: jurvetson / flickr (BY 2.0)

The "open models are a generation behind" line stopped being true in 2026. DeepSeek V4 Pro ties the closed frontier on agentic coding benchmarks. Kimi K2.6 sits at #4 overall on neutral leaderboards, open or closed. Qwen, GLM, and Llama each own a niche outright. For a large and growing set of workloads, the question is no longer "open or proprietary" but "which open model, under which license, for which job." Here is the lay of the land and how to choose.

Quick answer

There is no single best open-weight LLM in 2026, only the best fit for your job and license. Reach for DeepSeek V4 Pro (MIT) for serious agentic coding, Kimi K2.6 for top-tier general chat and reasoning, Qwen 3.5/3.6 (Apache 2.0) when you need the most permissive commercial license, Llama 4 Scout for ultra-long context up to 10M tokens, and GLM-5 (MIT) when you want permissive licensing plus strong code performance together. Shortlist by your hard constraints, then benchmark on your own tasks.

Key takeaways

  • DeepSeek V4 Pro (Max) tops several overall open leaderboards and ties the closed frontier on SWE-bench-style agentic coding.
  • Kimi K2.6 (Moonshot) leads the neutral Artificial Analysis Index among open models (#4 overall), a strong general-purpose pick.
  • Licensing is a real differentiator: Qwen (Apache 2.0), DeepSeek and GLM (MIT) are the most permissive for commercial use.
  • Llama 4 Scout owns ultra-long context at up to 10M tokens; nothing open matches it for document-scale work.
  • The right model depends on the job and the license, not a single overall score, benchmark on your own data before committing.

The 2026 open frontier, model by model

DeepSeek V4 Pro. The all-around leader on several open leaderboards and the standout for agentic coding, where it ties the closed frontier on SWE-bench-style tasks. Released under MIT, so commercial use is unrestricted. If you want one model that does most things well and codes seriously, start here.

Kimi K2.6 (Moonshot). Tops the neutral Artificial Analysis Index among open models and ranks #4 overall across open and closed. A strong general-purpose chat and reasoning pick when you want frontier-class quality without a closed API.

Qwen 3.5 / 3.6. The license-friendly workhorse. Qwen ships under Apache 2.0, the most permissive option, with a smaller dense coder (Qwen3.6-27B) that punches above its size and large mixture-of-experts variants for general use. If legal flexibility matters most, Qwen is the safe default.

GLM-5 / 5.1. The cleanest MIT license in the group and a top coding score (GLM-5 around 77.8% on SWE-bench Verified). A strong choice when you want permissive licensing and serious code performance together.

Llama 4 Scout / Maverick. Scout owns ultra-long context, up to 10M tokens, unmatched among open models for whole-codebase or whole-archive tasks. Maverick posts the highest MMLU (around 85.5%) among open models for general knowledge.

Mistral and Gemma. Still relevant for European-hosted and small-footprint deployments respectively, though they trail the leaders on raw benchmarks.

A comparison grid of open-weight LLM models and their strengths
Photo: Birmingham Museums Trust, Peter Reavill, 2018-10-30 14:14:20 / wikimedia (BY 2.0)

Here is the same field as a side-by-side, so you can match a model to a license and a strength at a glance:

ModelLicenseStandout strengthBest for
DeepSeek V4 ProMITTies closed frontier on agentic codingCoding, all-around work
Kimi K2.6Modified MIT#4 overall on Artificial Analysis IndexGeneral chat and reasoning
Qwen 3.5 / 3.6Apache 2.0Most permissive license, strong dense coderCommercial deployment, self-hosting
GLM-5 / 5.1MIT~77.8% SWE-bench VerifiedPermissive license plus coding
Llama 4 ScoutLlama licenseUp to 10M-token contextWhole-codebase, whole-archive tasks
Llama 4 MaverickLlama license~85.5% MMLUBroad general knowledge

Note that Llama 4 ships under Meta's community license, not a true open-source license. It carries an acceptable-use policy and a scale clause (companies above 700M monthly active users need a separate grant), so for unconditional commercial freedom the Apache 2.0 and MIT models are the cleaner picks.

Choosing by use case

The leaderboard is a shortlist, not an answer. Map to the job:

  • Agentic coding, DeepSeek V4 Pro or GLM-5.
  • General chat and reasoning, Kimi K2.6 or Llama 4 Maverick.
  • Most permissive license, Qwen (Apache 2.0), DeepSeek or GLM (MIT).
  • Ultra-long context, Llama 4 Scout (10M tokens).
  • Small, self-hosted coder, Qwen3.6-27B.

Tip

Read the actual license before you build on a model. Apache 2.0 and MIT let you fine-tune and deploy commercially with zero royalties. Some "open" models carry acceptable-use clauses or scale caps that matter for a production business. License is a feature.

The real cost is running them

Downloading weights is free; serving them is not. A 400B-parameter mixture-of-experts model needs serious GPU memory and a capable inference stack, and your throughput-per-dollar depends heavily on the engine. Which one you choose, vLLM, Ollama, or llama.cpp, changes latency and cost more than people expect, which is exactly the comparison in which inference engine to use in 2026. For smaller models and edge deployments, the calculus shifts again toward small language models and on-device agents.

Open weights also unlock the customization path that closed APIs gate off. Because you control the model, you can attach a LoRA adapter and shape behavior to your domain, the practical decision of when that pays off is in fine-tuning vs RAG vs prompting.

A quick selection process

    1. List your hard constraints: license type, max context, self-hosted or API, budget per million tokens.
    2. Shortlist two or three models that clear those constraints from the leaderboard.
    3. Benchmark each on 30 to 50 of your own real tasks, not generic benchmarks.
    4. Factor serving cost: model size times your inference engine's efficiency on your hardware.
    5. Pick the cheapest model that clears your quality bar, then revisit quarterly as the field moves.

Frequently asked questions

Are open-weight models as good as GPT or Claude in 2026?

On many benchmarks, yes. DeepSeek V4 Pro ties the closed frontier on agentic coding, and Kimi K2.6 ranks in the overall top five. Closed models still lead on some frontier tasks, but the gap is narrow and workload-dependent.

Which open model has the most permissive license?

Qwen under Apache 2.0, and DeepSeek and GLM under MIT, are the most permissive, letting you fine-tune and deploy commercially with no royalties. Always read the specific license, since some "open" models add usage clauses.

What if I need a huge context window?

Llama 4 Scout supports up to 10M tokens, far beyond other open models, making it the pick for whole-codebase or whole-archive tasks. For most workloads, though, a smaller context plus good retrieval is cheaper and more reliable.

Open weights or a hosted API?

Open weights win on cost at scale, data control, customization, and license freedom, but you own the serving complexity and GPU bill. Hosted APIs win on zero-ops convenience. Many teams use both, open models for high-volume workloads and a frontier API for the hardest tasks.

The takeaway

In 2026 the open ecosystem is genuinely competitive: DeepSeek leads coding, Kimi leads general quality, Qwen and GLM lead on licensing, and Llama leads on context. There is no single winner, only the best fit for your license needs, context requirements, and serving budget. Shortlist by constraint, benchmark on your data, and re-check quarterly, the order changes fast.

#ai#open-source#llm

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