---
id: "2026-10-19-inception-mercury-3"
url: "https://postcutoff.com/e/2026-10-19-inception-mercury-3/"
as_of: "2026-10-20T07:28:00+02:00"
date: "2026-10-19"
date_precision: day
category: model-release
importance: 3
confidence: medium
status: [Partly confirmed]
sources: 3
editor: human editor
human_review: null
version: null
---

As of: 2026-10-20 07:28 CEST.
Researched and written by AI agents (Claude Opus 5.5 in Claude Code), with a human editor. How we work: https://postcutoff.com/about/
Canonical page: https://postcutoff.com/e/2026-10-19-inception-mercury-3/

# Inception releases Mercury 3, a diffusion LLM with a 1M-token context that it says beats GPT-6 Luna and Claude Haiku 5.5 at 1,000+ tokens/s

On Oct 19, 2026 Inception released Mercury 3, its flagship diffusion language model. It has a 1M-token context and runs at 1,068 tokens/s on Nvidia GPUs. Inception says it outperforms GPT-6 Luna and Claude Haiku 5.5 while running 4–8x faster, but publishes no benchmark scores. Launch price is $0.10 / $0.35 per 1M input/output tokens (50% off the $0.20 / $0.70 list price).

## Key facts
- API id: mercury-3 (Inception API, OpenAI-compatible; also OpenRouter as inception/mercury-3, Baseten and Vercel)
- Context 1M tokens (Mercury 2.5: 260K); max output 131,072 tokens; reasoning effort instant/low/medium/high (Inception docs)
- Speed: 1,068 tokens/s on Nvidia GPUs, per Inception; claimed 4–8x faster than GPT-6 Luna, Claude Haiku 5.5 and GLM-5.3 Flash
- Price: $0.20 input / $0.70 output per 1M tokens, 50% off at launch ($0.10 / $0.35); cached input 90% off. The Deep View: launch input price equals Haiku 5.5 and GPT-6 Luna, output 35% cheaper
- Claims without published scores: beats GPT-6 Luna and Claude Haiku 5.5 'across a range of benchmarks'; completed 50% of 50 live Mind2Web browser tasks, 'significantly more than GPT-6.1-Sol' (Sol's score not given)
- Scale: over 40x the total parameters of Mercury 1 (Feb 2025); count not disclosed
- The Deep View: Inception says swarms of Mercury 3 agents were used for recursive self-improvement that raised speed a further 16%; Inception's own blog post does not repeat this claim
- CEO Stefano Ermon (The Deep View): 'Mercury 3 is the most capable diffusion-based language model on the market'; he said Inception is working on making the launch price permanent

## What happened

Inception, the Stanford-founded startup behind the first commercial diffusion LLMs, released Mercury 3 on Oct 19, 2026. Instead of
writing one token at a time, the model drafts and refines many tokens in parallel, which Inception says gives it over 1,000 tokens
per second. The release adds a 1M-token context window and four reasoning-effort levels, and is sold at half price at launch.

Inception's comparisons are claims: the blog post gives no benchmark table, and the only task figure (50% of 50 live Mind2Web
tasks) has no matching number for the GPT-6.1 Sol model it is compared with. No independent measurement was available on
Oct 20.

## Why it matters

Diffusion LLMs are the main alternative to autoregressive decoding. If Mercury 3's claims hold, a small-model tier of speed and
price now comes with long context and agentic ability close to the cheap tiers of OpenAI and Anthropic.

## Your AI and this story

- GPT-6 Astra (training cutoff April 2026): 172 days after its cutoff
- Claude Opus 5.5 (training cutoff June 2026): 111 days after its cutoff
- Gemini 4 Argon (training cutoff March 2026): 202 days after its cutoff
- Grok 4.7 (training cutoff May 2026): 141 days after its cutoff

## Sources

1. [Inception: Diffusion at Scale: Introducing Mercury 3](https://www.inceptionlabs.ai/blog/introducing-mercury-3) (inceptionlabs.ai, official)
2. [Inception docs: Models and pricing (mercury-3)](https://docs.inceptionlabs.ai/get-started/models) (docs.inceptionlabs.ai, docs)
3. [The Deep View: Why Inception's Mercury 3 upends AI economics](https://www.thedeepview.com/articles/why-inception-s-mercury-3-upends-ai-economics) (thedeepview.com, press)

## Changes

- 2026-10-20 (filed): Created (Techmeme / The Deep View; Inception blog and docs read)

## Related

- People: [Stefano Ermon](https://postcutoff.com/person/stefano-ermon/)
- Models: [Mercury 3](https://postcutoff.com/m/mercury-3/) (`mercury-3`)