Inception launched Mercury 3 on October 19, 2026, positioning it as a faster, more capable diffusion language model. Its headline claims include 1,068 tokens per second on NVIDIA GPUs and benchmark advantages over GPT-6 Luna and Claude Haiku 5.5—but those comparisons should be treated as company claims, not independent validation.
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How Mercury 3 generates text differently
A standard autoregressive language model generates text sequentially, predicting the next token from the tokens already produced. Mercury 3 uses a diffusion approach: it generates multiple token positions in parallel, then refines the draft across successive passes.
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That difference is central to Inception’s speed pitch. Instead of waiting for each token to be produced one after another, Mercury 3 works on a batch of text positions at once. The launch materials report a speed of 1,068 tokens per second on NVIDIA GPUs.
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The launch claims: speed, benchmarks and scale
Inception says Mercury 3 outperforms GPT-6 Luna and Claude Haiku 5.5 across a range of benchmarks while running four to eight times faster. The company’s reported speed comparison puts Mercury 3 at 1,068 tokens per second.
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20 These figures describe Inception’s claims; they do not establish that the same advantage will hold across workloads or independent testing.
The model is also reported to be more than 40 times the size of Mercury 1, while maintaining speeds above 1,000 tokens per second. Its context window expands from Mercury 2.5’s 260,000 tokens to 1 million.
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17 Inception’s launch was described as its fourth model release since Mercury 1 launched in June 2025.
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Early browser-agent result
Inception and coverage of its launch report that Mercury 3 completed 50% of 50 live Mind2Web tasks—25 tasks—and performed better than GPT-6.1-Sol at the same step count.
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30 This is a specific reported test result, not proof that the model will outperform in every browser-agent setting.
Pricing and availability
The listed prices are $0.20 per million input tokens and $0.70 per million output tokens. A 50% launch discount brings those rates to $0.10 and $0.35, respectively. Cached input tokens are listed at 90% off standard input pricing.
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Mercury 3 is available through Inception’s API, Baseten, OpenRouter and Vercel; the API is described as OpenAI-compatible.
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What remains to be verified
The main performance figures and comparisons are presented as Inception’s claims. Launch coverage also noted that independent benchmark validation was not available at the time.
11 That makes the announcement useful as a statement of what the company says it has built, but not a settled independent verdict on Mercury 3’s quality or speed relative to competing models.
The clearest takeaway is that Mercury 3 applies parallel generation and iterative refinement to a larger model and a longer context window, with Inception claiming a substantial speed advantage. Independent comparisons will be needed to determine how reliably those headline results translate to real-world use.