June 15, 2026

What is ZDR Chat?

A deep dive into ZDR Chat — a serverless, browser-local AI chat app that puts your privacy first.

introprivacyoverview

Have you used an AI chat app and wondered where your conversations go? Most AI chat apps send your data to their servers — storing, analyzing, and training on your conversations. ZDR Chat takes a radically different approach.

The Problem

When you chat with most AI assistants:

  • Your conversation history is stored on the provider’s servers
  • Your API keys are managed by their backend
  • Your usage patterns can be tracked and analyzed
  • Your data persists even after you close the tab

For privacy-conscious users, this is unacceptable.

The Solution: ZDR Chat

ZDR Chat (Zero Data Retention) is a serverless, BYOK (Bring Your Own Key) chat application that runs entirely in your browser. Here’s what makes it different:

🔐 Browser-Local by Default

Everything lives in your browser’s IndexedDB:

  • Conversation history — stored locally
  • API key — stored locally
  • Preferences — stored locally

When you close the tab, the connection to the model is gone. Your data remains in your browser until you choose to clear it.

🏠 No Backend, No Servers

ZDR Chat is a static PWA deployed to Cloudflare Pages. There is no backend server, no database, no user accounts, no sign-up flow. The entire application is static HTML, CSS, and JavaScript.

🔑 Bring Your Own Key

You paste your OpenRouter API key directly into the app. It’s never sent anywhere except directly to OpenRouter when you make a request. We never see your key.

🧠 300+ Models

The app connects to OpenRouter, giving you access to 300+ models — from the latest frontier models to specialized code generators, vision models, and free options. The model picker organizes them into neat buckets so you always find the right one.

How ZDR Enforcement Works

At the OpenRouter level, ZDR (Zero Data Retention) can be enforced three ways:

  1. Account-level setting — Enable ZDR for all requests from your account
  2. Guardrail — A safety catch that prevents per-request opt-outs
  3. Per-request header — The X-ZDR: 1 header sent with every request

With all three configured, your data is ZDR-guaranteed at the network layer.

Ready to try it?

No sign-up, no account creation. Just open the app, paste your OpenRouter key, and start chatting. Your privacy is preserved from the first message.

ZDR Chat is an independent, open-source project. We’re not affiliated with OpenRouter.ai — we don’t resell their services, earn commissions, or track your usage. We built this because private AI should be accessible.