Side-by-side comparison of AI visibility scores, market position, and capabilities
Raised $175M Series B (2025) at $4.5B val led by Sequoia. Founded by ex-Salesforce CEO Bret Taylor and Clay Baird. AI agents handling millions of customer service conversations for enterprise brands.
Sierra AI is a conversational AI platform for enterprise customer service and sales, building AI agents that handle complex customer interactions across support, returns, troubleshooting, and sales workflows for major consumer and enterprise brands. The company raised $175 million in Series B financing in 2025, led by Sequoia at a $4.5 billion valuation. Sierra was founded by Bret Taylor—former Co-CEO of Salesforce, former CTO of Facebook, and chair of OpenAI's board during the November 2023 crisis—and Clay Baird, with the thesis that enterprise-grade conversational AI requires different architecture than general-purpose chatbots.
ChatGPT surpassed 400M weekly active users in February 2025 and launched GPT-4o with voice, image, and real-time reasoning — the world's most-used AI product.
ChatGPT is OpenAI's flagship AI assistant, launched in November 2022 and credited with igniting mainstream consumer adoption of generative AI. It crossed 100 million users in two months — the fastest consumer product to do so in history — and reached 400 million weekly active users by February 2025. Available as a free web and mobile app with a ChatGPT Plus subscription ($20/month) unlocking GPT-4o, advanced voice mode, image generation, and longer context.
Monitor how your brand performs across ChatGPT, Gemini, Perplexity, Claude, and Grok daily.