Comparisons
Closed-source LLMs compared
Six proprietary LLM APIs, scored uniformly on the same seven criteria - with a source link and date for every entry, so you can verify the numbers yourself. This category is aimed at developers and technical decision-makers building an application on an API - not end users of a finished chat app (see our "AI Chat Assistants" category for that). Switch between the individual and business perspective at the top of the table. At the bottom you'll find scenario recommendations instead of a single "winner": which API fits depends on your specific situation.
A comparison of closed-source LLM APIs weighs offerings like GPT, Claude, Gemini, Grok, Cohere and Kimi K3 from a developer's perspective - from price per token to rate limits to enterprise SLAs - for anyone building their own application on an API.
How we score →At a glance
Calculated automatically from the scores below - the provider highlighted in green has the highest average score across all criteria, not an editorial pick. Toggle providers in the legend on or off.
Last data review: 10/19/2026
Could not be verified automatically in the last run: Cohere - those figures date from 08/17/2026.
Click a row for strengths, weaknesses, and our take.
| Tool | Price | Value for money | Privacy & hosting | Performance & context window | Rate limits & availability | Ecosystem & tooling | Multimodality | Enterprise readiness & compliance | Ideal for | Learn more |
|---|---|---|---|---|---|---|---|---|---|---|
GPT (API) OpenAI | $10/M input · $50/M output tokens (flagship GPT-6 Astra) · GPT-6.1 Sol $2/$10 · GPT-6 Luna $0.10/$0.50 · predecessor GPT-5.6 Sol $4/$20 | 5 of 5 | 4 of 5 | 5 of 5 | 4 of 5 | 5 of 5 | 4 of 5 | 5 of 5 | Developers wanting strong performance at a moderate price +1 | |
Claude (API) Anthropic | $4/M input · $20/M output tokens (Opus 5.5, recommended by Anthropic as the default starting point) · Fable 5.1 $10/$50 · Sonnet 5.5 $2/$10 · Haiku 5.5 from $0.10/$0.50 | 3 of 5 | 2 of 5 | 5 of 5 | 3 of 5 | 5 of 5 | 2 of 5 | 4 of 5 | Coding- and analysis-heavy projects needing maximum text quality +1 | |
Gemini (API) | $2/M input · $10/M output tokens (Gemini 4 Argon, introductory price through 2026-11-30, then $4/$20) · Gemini 3.1 Pro Preview $2/$12 (up to 200k tokens, then $4/$18) · cheaper Flash tiers | 4 of 5 | 4 of 5 | 5 of 5 | 3 of 5 | 3 of 5 | 5 of 5 | 5 of 5 | Multimodal projects (image, audio, video in one model) +1 | |
Grok (API) xAI | $2/M input · $6/M output tokens (<200k tokens; unchanged since 4.5, also applies to 4.6 and 4.7) · EU availability of 4.7 not documented by xAI (only US regions listed) · predecessor 4.3 ($1.25/$2.50) | 5 of 5 | 2 of 5 | 4 of 5 | 3 of 5 | 4 of 5 | 4 of 5 | 2 of 5 | Price-conscious developers outside the EU wanting an OpenAI-compatible API +1 | |
Cohere Cohere | Command A+ Apache 2.0/open weights per May 2026 research (not re-confirmed) · Model Vault from $3/hour or $2,000/month (Embed 5), Parse 5 from $4/hour or $2,500/month | 3 of 5 | 5 of 5 | 2 of 5 | 3 of 5 | 4 of 5 | 2 of 5 | 5 of 5 | RAG-/retrieval-heavy projects needing rerank/embed +1 | |
Kimi K3 Moonshot AI | $0.30/M input (cache hit) · $3/M input (cache miss) · $15/M output tokens · weights now open (Kimi K3 License) | 4 of 5 | 1 of 5 | 5 of 5 | 2 of 5 | 2 of 5 | 3 of 5 | 1 of 5 | Price-conscious developers with non-critical data wanting maximum raw performance +1 | |
Which tool fits you?
Strong performance at a moderate price (coding/analysis)
GPT (API)
GPT-6.1 Sol delivers near-flagship Astra performance per OpenAI for $2/$10 - 52 points on Artificial Analysis (as of October 2026).
Building agents and tools with MCP
Claude (API)
The origin and deepest integration of the MCP standard, plus the highest score on the Artificial Analysis leaderboard (Opus 5.5: 58, as of October 2026).
Multimodal applications from a single provider
Gemini (API)
The broadest multimodality (image, video, audio, four image-generation tiers) and the best certification standing.
Maximum cost efficiency outside the EU
Grok (API)
Still the cheapest flagship pricing tier among the APIs - EU customers should clarify Grok 4.7's EU availability before use.
A cheap, high-performance API for non-critical data
Kimi K3
A high SWE-bench score (93.4%) at a low cost - but without certifications or EU hosting, so suitable only for non-critical data.
Key takeaways
- GPT (API) has a new flagship in GPT-6 Astra ($10/$50); GPT-6.1 Sol ($2/$10) delivers near-Astra performance per OpenAI at a fifth of the price. On Artificial Analysis, GPT-6 Astra scores 53 and GPT-6.1 Sol 52 (as of October 2026) - the top spot there belongs to Claude Opus 5.5 at 58.
- Claude (API) fields the strongest model on the Artificial Analysis leaderboard with Opus 5.5 ($4/$20, 58 points as of October 2026), which Anthropic itself recommends as the default starting point; Fable 5.1 ($10/$50) remains the special case for the most demanding reasoning and agentic work, but without a zero-data-retention option.
- Kimi K3 (Moonshot AI) scores 93.4% on SWE-bench (archived vals.ai leaderboard) and 44 points on Artificial Analysis (as of October 2026) at a fraction of the cost - but the hosted API has no certifications, EU hosting, or ZDR option. The weights have since been published on Hugging Face (under Moonshot's own Kimi K3 License).
- Grok (API) is now at version 4.7 (still $2/$6; 46 points on Artificial Analysis, as of October 2026). Whether 4.7 is usable in the EU isn't stated in xAI's docs (only US regions are listed) - EU customers should clarify that before using it.
- Cohere surprisingly pivoted to open weights with Command A+ (Apache 2.0, free) - but raw performance remains the weakest in this comparison.
- Gemini (API) has a new flagship in Gemini 4 Argon (introductory price $2/$10, $4/$20 from December 1, 2026) with 53 points on Artificial Analysis, and still offers the broadest multimodality and best certification coverage among the six APIs.
→ Self-host, use an API, or buy a ready-made solution? Build vs. buy vs. API
→ Find the right approach for your own data: RAG-or-Fine-Tuning Finder
Frequently asked questions
Which LLM API is best for coding applications?
On the Artificial Analysis leaderboard, Claude Opus 5.5 leads (58 points, as of October 2026), followed by GPT-6 Astra and Gemini 4 Argon (53 each), Grok 4.7 (46), and Kimi K3 (44). The SWE-bench Verified benchmark on vals.ai is archived and no longer maintained for new models. Claude is also the origin of the MCP (Model Context Protocol) standard for tool integrations and still has the deepest ecosystem there.
Which LLM API is the cheapest?
Grok (API) with 4.7 ($2/$6) still has the cheapest flagship pricing per million tokens among the APIs with a full enterprise offering - EU availability should be clarified with xAI before use. Kimi K3 undercuts Grok on cache-hit input pricing, but comes in above it on output pricing.
Is there an LLM API with on-premise deployment for regulated industries?
Cohere is still the only option among the six APIs compared with true private/on-premise deployment (Model Vault, BYOC) - since May 2026 also with open weights (Command A+, Apache 2.0) for anyone who wants to self-host.
Is Kimi K3 an open or a closed model?
Both: Moonshot AI has since published the Kimi K3 weights on Hugging Face (repository moonshotai/Kimi-K3, 2.8T total parameters, 104B active, under the custom Kimi K3 License), and the hosted API continues alongside. The license is neither Apache nor MIT - check the terms before commercial use. Kimi K3 sits in this category because of its API evaluation; whether we additionally list it under the open-source LLMs is still under review.
Why is Cohere listed here even though Command A+ has open weights?
Cohere is evaluated in this category primarily for its API/enterprise business model (Model Vault, managed Rerank/Embed services, a sales process for enterprise terms), not for the weights themselves. Unlike the models in our open-source category, Cohere's managed platform is the focus here - Command A+'s open weights are an additional self-hosting option, not a business-model pivot.
What's the difference between this category and "AI Chat Assistants"?
This category evaluates APIs from a developer's perspective (price per token, context window, SDKs, rate limits) for building custom applications. The "AI Chat Assistants" category instead compares the finished consumer chat apps (ChatGPT, Claude.ai, the Gemini app, etc.) for end users.