Releasing an Open Source User Agent Lookup Table

I'm working on PageviewsOnline as a side project. The goal is simple: privacy-first web analytics that focus on pageviews, not people.

As part of building PageviewsOnline, I recently released a user agent lookup table as an open source project.

This lookup table is used to turn raw user agent strings into basic, high-level info like browser and operating system. It’s not meant to be perfect or super advanced — it’s meant to be fast, predictable, and good enough for simple analytics.

Here’s why I decided to open source it.

• Trust and transparency
  Analytics and user agents can feel sketchy. By open sourcing this, anyone can see exactly how it works. No hidden logic, no tracking tricks, no guessing.

• Performance over cleverness
  The lookup is based on normalized strings that can be hashed and compared directly. This is much faster and more predictable than complex regular expressions, especially at scale.

• JSON makes it language-agnostic
  The dataset is stored as JSON. That means it's easy to inspect, version-control, and use from almost any programming language without extra tooling.

• Simple by design
  This is not a sophisticated detection engine. It doesn't aim for perfect accuracy. It aims to be fast, reliable, and stable while providing basic analytics that don’t break when user agents change.

• Open and community-driven
  Since it’s open source, anyone can use it, fork it, or contribute improvements. My hope is that it slowly gets better over time through real-world usage and community input.

This project is actively used in production, but it’s also useful on its own.

Open sourcing it felt like the right fit for how I want to build PageviewsOnline - simple, honest, and privacy-first.

https://github.com/pageviewsonline/user-agent-lookup-table

// Christoffer