IonRouter

What it does

IonRouter is a Y Combinator-backed startup (W26) providing high-throughput, low-cost inference solutions for AI models. Its core technology is the IonAttention engine, a custom inference stack built from the ground up for NVIDIA Grace Hopper superchips. The engine multiplexes multiple models on a single GPU, swaps models in milliseconds, and adapts to traffic in real time. IonRouter claims throughput of 7,167 tokens per second on a single GH200 for Qwen2.5-7B, compared to ~3,000 tok/s from a top inference provider. The platform supports any model—including finetunes, custom LoRAs, and open-source models—with dedicated GPU streams, no cold starts, and per-second billing. It offers an OpenAI-compatible API, requiring only a one-line change to switch from OpenAI. Pricing is per million tokens with no idle costs.

Who it is for

IonRouter targets teams building real-time AI applications that demand high performance and low latency. Use cases include robotics perception (real-time VLM), multi-stream video surveillance, game asset generation, and AI video pipelines (text-to-video and image-to-video). The platform is designed for developers who want to deploy custom models or use popular open-source models without GPU expertise. A case study highlights running five vision-language models on a single GPU, processing 2,700 video clips with concurrent users and sub-1-second cold starts.

Why it matters

Inference cost and latency are major bottlenecks for deploying AI at scale. IonRouter addresses this by combining custom hardware (Grace Hopper) with a proprietary software stack (IonAttention) to maximize throughput and minimize cost. The ability to multiplex models on a single GPU and swap in milliseconds reduces idle time and improves utilization. For teams running multiple models or real-time pipelines, this can significantly lower infrastructure costs while maintaining performance. The OpenAI-compatible API also reduces migration friction.

Launch signal

IonRouter launched on Hacker News as a YC W26 startup. The website prominently features the tagline "High throughput, low cost inference" and offers $5 in free credits via Discord. The company is part of NVIDIA Inception, indicating partnership with NVIDIA. The site includes a playground for testing models and a case study blog post.

Brand and naming

The name "IonRouter" suggests speed and routing—"Ion" implying fast, charged particles, and "Router" indicating intelligent traffic management. The brand positions itself as a high-performance alternative to generic cloud inference providers, emphasizing its custom engine and hardware partnership with NVIDIA. The tagline is clear and benefit-driven. The visual identity uses a dark theme with neon accents, conveying a tech-forward, performance-oriented image.