# LLM APIs: which vendors AI models recommend (September 2026)

Source: Memetik Index, https://www.memetik.ai/index/llm-apis
Field: AI infra. Edition: 2026-09. Run: 2026-09-02.
Method: 5 fixed buyer prompts sent once each to 10 current models (GPT-5.6 Sol, GPT-5.6 Terra, GPT-5.6 Luna, Claude Opus 5, Claude Sonnet 5, Claude Fable 5, Gemini 3.6 Flash, Gemini 3.5 Flash, Sonar Pro, Sonar Reasoning Pro) via their APIs with web search enabled. 50 answers. Answer share = fraction of answers naming the vendor. Named first = fraction where it was the first tracked vendor named.

**OpenAI leads** with 100% answer share (named in 50 of 50 answers) and was named first in 66%. Google follows at 100%. 15 vendors were named at least once.

## Answer share

| # | Vendor | Answer share | Named first | Mentions | Models |
|---|---|---|---|---|---|
| 1 | OpenAI | 100% | 66% | 50/50 | GPT-5.6 Sol, ChatGPT, GPT-5.6 Luna, Claude Opus 5, Claude, Claude Fable 5, Gemini, Gemini 3.5 Flash, Perplexity, Sonar Reasoning Pro |
| 2 | Google | 100% | 4% | 50/50 | GPT-5.6 Sol, ChatGPT, GPT-5.6 Luna, Claude Opus 5, Claude, Claude Fable 5, Gemini, Gemini 3.5 Flash, Perplexity, Sonar Reasoning Pro |
| 3 | Anthropic | 92% | 28% | 46/50 | GPT-5.6 Sol, ChatGPT, GPT-5.6 Luna, Claude Opus 5, Claude, Claude Fable 5, Gemini, Gemini 3.5 Flash, Perplexity, Sonar Reasoning Pro |
| 4 | DeepSeek | 66% | 2% | 33/50 | GPT-5.6 Luna, Claude Opus 5, Claude, Claude Fable 5, Gemini, Gemini 3.5 Flash, Perplexity, Sonar Reasoning Pro |
| 5 | OpenRouter | 54% | 0% | 27/50 | Claude Opus 5, Claude, Claude Fable 5, Gemini, Gemini 3.5 Flash, Perplexity, Sonar Reasoning Pro |
| 6 | Amazon Bedrock | 52% | 0% | 26/50 | GPT-5.6 Sol, ChatGPT, GPT-5.6 Luna, Claude Opus 5, Claude, Claude Fable 5, Gemini, Gemini 3.5 Flash, Perplexity, Sonar Reasoning Pro |
| 7 | Groq | 50% | 0% | 25/50 | Claude Opus 5, Claude, Claude Fable 5, Gemini, Gemini 3.5 Flash, Perplexity, Sonar Reasoning Pro |
| 8 | Azure OpenAI | 48% | 0% | 24/50 | GPT-5.6 Sol, ChatGPT, GPT-5.6 Luna, Claude Opus 5, Claude, Claude Fable 5, Gemini, Gemini 3.5 Flash, Perplexity, Sonar Reasoning Pro |
| 9 | Mistral | 44% | 0% | 22/50 | GPT-5.6 Sol, GPT-5.6 Luna, Claude Opus 5, Claude, Claude Fable 5, Gemini, Gemini 3.5 Flash, Perplexity, Sonar Reasoning Pro |
| 10 | Together | 38% | 0% | 19/50 | Claude Opus 5, Claude, Claude Fable 5, Gemini, Gemini 3.5 Flash, Sonar Reasoning Pro |
| 11 | Meta Llama | 34% | 0% | 17/50 | Claude Opus 5, Claude, Gemini, Gemini 3.5 Flash, Sonar Reasoning Pro |
| 12 | LiteLLM | 34% | 0% | 17/50 | GPT-5.6 Luna, Claude Opus 5, Claude, Claude Fable 5, Gemini, Gemini 3.5 Flash, Sonar Reasoning Pro |
| 13 | Qwen | 16% | 0% | 8/50 | Claude Opus 5, Claude, Gemini, Gemini 3.5 Flash, Sonar Reasoning Pro |
| 14 | xAI | 8% | 0% | 4/50 | GPT-5.6 Sol, Claude Opus 5, Claude Fable 5 |
| 15 | Cohere | 2% | 0% | 1/50 | GPT-5.6 Sol |

## By model

- **GPT-5.6 Sol** (OpenAI, gpt-5.6-sol, 5 answers): OpenAI 100%, Google 100%, Amazon Bedrock 80%, Anthropic 40%, Azure OpenAI 20%
- **GPT-5.6 Terra** (OpenAI, gpt-5.6-terra, 5 answers): OpenAI 100%, Google 100%, Anthropic 80%, Amazon Bedrock 40%, Azure OpenAI 20%
- **GPT-5.6 Luna** (OpenAI, gpt-5.6-luna, 5 answers): OpenAI 100%, Google 100%, Anthropic 100%, Mistral 80%, DeepSeek 40%
- **Claude Opus 5** (Anthropic, claude-opus-5, 5 answers): OpenAI 100%, Google 100%, Anthropic 100%, DeepSeek 100%, OpenRouter 60%
- **Claude Sonnet 5** (Anthropic, claude-sonnet-5, 5 answers): OpenAI 100%, Google 100%, Anthropic 100%, Together 100%, DeepSeek 80%
- **Claude Fable 5** (Anthropic, claude-fable-5, 5 answers): OpenAI 100%, Google 100%, Anthropic 100%, OpenRouter 100%, Mistral 80%
- **Gemini 3.6 Flash** (Google, gemini-3.6-flash, 5 answers): OpenAI 100%, Google 100%, Anthropic 100%, DeepSeek 100%, OpenRouter 100%
- **Gemini 3.5 Flash** (Google, gemini-3.5-flash, 5 answers): OpenAI 100%, Google 100%, Anthropic 100%, DeepSeek 100%, OpenRouter 100%
- **Sonar Pro** (Perplexity, sonar-pro, 5 answers): OpenAI 100%, Google 100%, Anthropic 100%, DeepSeek 80%, OpenRouter 40%
- **Sonar Reasoning Pro** (Perplexity, sonar-reasoning-pro, 5 answers): OpenAI 100%, Google 100%, Anthropic 100%, DeepSeek 100%, Meta Llama 100%

## Sources the models cited

- syncfusion.com: 140
- braintrust.dev: 88
- dataiku.com: 59
- ofox.ai: 56
- futureagi.substack.com: 45
- reddit.com: 45
- pecollective.com: 41
- medium.com: 32
- fireworks.ai: 26
- edenai.co: 22
- tokenmix.ai: 22
- ai.google.dev: 21
- morphllm.com: 19
- wireflow.ai: 17
- requesty.ai: 15

## Prompts

1. What is the best LLM API to build a product on for a developer? Name specific products.
2. Which LLM API to build a product on would you recommend to a developer in 2026?
3. Compare the top LLM API to build a product on options right now.
4. I'm a developer and I need a LLM API to build a product on. What should I use and why?
5. Best LLM API to build a product on for an AI startup balancing cost and quality?

## Tracked but never named

None.

Raw answers: https://www.memetik.ai/index/llm-apis (every answer published in full). Chart image: https://www.memetik.ai/charts/llm-apis.png. Licence: CC BY 4.0, credit "Memetik Index".