Inception: Mercury 2.5 Preview
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Mercury 2.5 Preview is a diffusion-based reasoning language model from Inception Labs, refining tokens in parallel rather than generating them one at a time. It preceded the general release of Mercury 2.5 and followed Mercury 2, adding tunable reasoning levels, parallel tool calls, and schema-aligned JSON output.
Inception reports throughput of 1,107 tokens per second on standard GPUs and a 10+ point jump in intelligence over Mercury 2. It says quality is comparable to cost-optimized models such as GPT-5.6 Luna (Low), Gemini 3.5 Flash-Lite, and Claude Haiku 4.5.
With a 260K context window and 65,536 max output tokens, it targets production workloads where latency compounds, such as search agents, voice pipelines, and coding subagents. It is available through OpenRouter with an OpenAI-compatible API, priced at $0.04 per million input tokens and $0.15 per million output tokens.
Context Window 260K
tokens
Max Output 66K
tokens
Input Cost $0.04
per million tokens
Output Cost $0.15
per million tokens
Release Date Aug 31, 2026
Code Example
Add AI to your app with the Puter.js AI API, no API keys or setup required.
// npm install @heyputer/puter.js
import { puter } from '@heyputer/puter.js';
puter.ai.chat("Explain quantum computing in simple terms").then(response => {
document.body.innerHTML = response.message.content;
});
<html>
<body>
<script src="https://js.puter.com/v2/"></script>
<script>
puter.ai.chat("Explain quantum computing in simple terms").then(response => {
document.body.innerHTML = response.message.content;
});
</script>
</body>
</html>
More AI Models From Inception
Mercury 2.5
Mercury 2.5 is a diffusion language model from Inception Labs. Unlike autoregressive models that emit one token at a time, it generates and refines tokens in parallel. Inception reports 1,107 tokens per second on standard GPUs, and says quality is comparable to cost-optimized models such as GPT-5.6 Luna (Low), Gemini 3.5 Flash-Lite, and Claude Haiku 4.5. Reported benchmark figures include 79% on GPQA Diamond and 77% on IFBench. Independent benchmark coverage was not published at release, so those numbers are Inception's own. Through the API it supports tunable reasoning, parallel tool calls, and schema-aligned JSON output. With a 260K context window and 65,536 max output tokens, it targets latency-sensitive work such as search and RAG pipelines that fire many calls per request, voice agents, and coding-assistant tasks like context compaction and routing.
ChatMercury 2
Mercury 2 is a diffusion-based reasoning language model from Inception Labs that refines all tokens in parallel rather than generating them sequentially, achieving over 1,000 tokens per second — roughly 5x faster than speed-optimized competitors like Claude Haiku and GPT-5 Mini at comparable quality. On reasoning benchmarks, Mercury 2 scores 91.1 on AIME 2025 and 73.6 on GPQA. It also placed second on the Copilot Arena leaderboard for quality while ranking first for speed overall. With a 128K context window, it is purpose-built for latency-sensitive applications — real-time assistants, high-throughput pipelines, and cost-conscious production workloads where reasoning capability matters.
Frequently Asked Questions
Mercury 2.5 Preview is no longer available through Puter.js. Explore other AI models for alternatives.
| Price per 1M tokens | |
|---|---|
| Input | $0.04 |
| Output | $0.15 |
Mercury 2.5 Preview was created by Inception and released on Aug 31, 2026.
Mercury 2.5 Preview supports a context window of 260K tokens. For reference, that is roughly equivalent to 520 pages of text.
Mercury 2.5 Preview can generate up to 66K tokens in a single response.
Yes — the Mercury 2.5 Preview API works with any JavaScript framework, Node.js, or plain HTML through Puter.js. Just include the library and start building. See the documentation for more details.
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