# Perplexity launches Photon engine, dropping p99 latency to 65 ms

> Perplexity's new Rust‑based retrieval engine, Photon, reduces 99th‑percentile response time from 800 ms to 65 ms for its search API.

Oossa · 2026-09-30 · https://oossa.com/en/perplexity-launches-photon-engine-dropping-p99-latency-to-65-ms

Perplexity has rolled out Photon, a retrieval and ranking engine it built in Rust. The engine replaces a forked open‑source component and now handles all of Perplexity’s production search traffic. Photon also powers a new Fast Search mode in the Perplexity Search API, giving developers quicker answers. The company says the p99 latency – the time 99% of requests take – fell from about 800 ms to 65 ms.

## The facts

- p99 latency reduced from 800 ms to 65 ms
- Photon launched Sep 30 2026

## Why it matters

Faster search responses make AI‑driven answers feel more immediate for users and can lower cloud costs for developers.

## Sources & references

1. [Perplexity Introduces Photon: A Rust-Based Retrieval Engine That Cuts p99 Latency From 800 ms to 65 ms](https://www.marktechpost.com/2026/09/30/perplexity-introduces-photon-a-rust-based-retrieval-engine-that-cuts-p99-latency-from-800-ms-to-65-ms/) – MarkTechPost, 2026-09-30

Last updated: 2026-09-30