DEV Community

Arthur Turing
Arthur Turing

Posted on

I Built a Postcode-Level Broadband Comparison Tool for Every UK Postcode

Most broadband comparison sites show you plans. They don't show you what speed you'll actually get at your address.

I built Broadband Compare UK to fix that. It uses real Ofcom data to show postcode-level broadband availability, speeds, and coverage across the UK.

What it does

Every postcode page shows:

  • Broadband availability from Ofcom Connected Nations 2025
  • Real-world speeds from Ookla Speedtest data
  • House prices from Land Registry
  • Crime stats from Police.uk
  • School ratings from GIAS/Ofsted
  • Transport links, GP surgeries, EV charging, flood risk, air quality, and more

Over 500,000 postcodes are live right now. The full 1.7 million will be done this week.

The stack

  • Next.js 16 with ISR (Incremental Static Regeneration)
  • Neon PostgreSQL for all data (2.9GB and growing)
  • Tailwind v4 for styling
  • Vercel for hosting
  • 13 free UK government data sources stitched together per postcode

The data pipeline

The hardest part was not building the UI. It was ingesting and normalising data from 13 different government APIs, each with its own format, rate limits, and quirks.

Ofcom publishes broadband data as 121 separate CSV files. The Police API rate-limits to 1 request per second. Land Registry data needs SPARQL queries. The Environment Agency flood risk API only covers England.

I wrote a pipeline that processes each postcode prefix in parallel. Five batches running simultaneously. Each batch handles geocoding, broadband data, house prices, crime, schools, transport, GP surgeries, EV charging, council tax, EPC ratings, demographics, and deprivation indices.

Why I built it

When I moved house, I checked schools, crime, and transport. I forgot to check broadband. Ended up with 15Mbps in an area where the next street had 900Mbps.

Most people make the same mistake. Broadband Compare UK puts all the data on one page so you don't have to check five different government websites.

Try it

The site is live at broadbandcompareuk.com. Pick any postcode. Every page is free, no sign-up required.

Would love feedback from the dev community, especially on the data pipeline approach. Happy to answer questions about working with UK government open data.

Top comments (0)