How to Use BGrid

Complete guide to navigating and sharing locations using the hierarchical coordinate system.

Launch the map

🗺️ What is BGrid?

BGrid is a hierarchical coordinate system that divides the entire Earth's surface into a grid of parcels. Unlike traditional latitude and longitude, BGrid uses recursive subdivision where each level divides a parcel into exactly 2048 parcels.

You can reference any location on Earth using either:

  • Numbers: numeric identifiers (1–2048) for each parcel at each level
  • BIP39 Words: memorable words from the BIP39 wordlist
  • Decimal Degrees (DD): traditional latitude and longitude

🎯 Getting Started

Basic navigation

Desktop:

  • Pan: click and drag the map
  • Zoom: mouse wheel or the +/− buttons
  • Select: click any grid cell to drill into it
  • Up one level: the ↩ button on the map
  • Reset: click the BGrid logo to return to the world view

Mobile / touch:

  • Pan: drag with one finger
  • Zoom: pinch with two fingers
  • Select: tap a grid cell
  • Controls: tap the menu (☰) to open the panel

Interface overview

The control panel contains:

  • Location information: current level, BGrid value and decimal degrees
  • Language selector: the BIP39 wordlist language
  • Display format: Numbers, Words or DD
  • Grid lines toggle: show or hide the grid overlay
  • Converter: turn lat/lon into a BGrid reference

📏 Precision Levels

BGrid starts at Level 0 (the whole Earth) and refines down to Level 4. Each level multiplies precision by 2048.

  • L1: countries / large regions (~625 km per cell)
  • L2: cities / districts (~10–20 km)
  • L3: blocks / buildings (~300 m)
  • L4: address level (~5–10 m)

Tip: start at a lower level for general areas and increase precision as needed — higher levels need longer coordinate strings.

🔢 Display Formats

1. Numbers

Numeric parcel IDs separated by commas, e.g. 1024,512,1847. Best for computing, APIs and databases.

2. Words (BIP39)

The same path expressed as memorable words, e.g. middle,drift,weapon. Best for verbal communication and memorization.

3. Decimal Degrees (DD)

The center of the selected parcel as latitude, longitude, e.g. 48.858283, 2.294555. Best for GPS devices and existing mapping software.

Switch formats with the selector in the panel — the URL updates automatically so the format is preserved when you share it.

📍 Coordinate Converter

Transform lat/lon into a BGrid reference:

  1. Enter coordinates as lat, lon (e.g. 40.7128, -74.0060)
  2. Select a level (L1–L4)
  3. Convert — the map centers on the location and shows its BGrid value

Latitude ranges −90…+90, longitude −180…+180.

Places to try: Eiffel Tower 48.858370, 2.294481 · Sydney Opera House -33.856784, 151.215297 · Taj Mahal 27.175015, 78.042155.

🔗 Sharing Locations

Every selection has a unique URL encoding the location, format and level, so recipients see exactly what you see. Tap the share button to use your device's native share sheet, or fall back to copying the link to the clipboard.

URLs are human-readable:

  • https://maps.bgrid.org/?n=1024,512,1847 (numbers)
  • https://maps.bgrid.org/?en=middle,drift,weapon (words)
  • https://maps.bgrid.org/?dd=48.858283,2.294555 (decimal degrees)

⚙️ Advanced Features

Grid lines

Toggle the grid overlay to show or hide parcel boundaries at the current level.

Languages (BIP39)

Wordlists are available in 8 languages: 🇺🇸 English · 🇪🇸 Español · 🇫🇷 Français · 🇧🇷 Português · 🇨🇳 中文 · 🇨🇿 Čeština · 🇮🇹 Italiano · 🇰🇷 한국어.

Keyboard (desktop)

  • + / −: zoom in / out
  • Arrow keys: pan the map

🔧 Technical Details

BGrid recursively subdivides the Earth: at each level every parcel splits into 2048 sub-parcels (alternating 64×32 and 32×64), numbered 1–2048. A coordinate is the path of those indices.

Why 2048? It is 211 and exactly the BIP39 wordlist size, giving a perfect 1:1 number↔word mapping with no gaps.

The grid math runs entirely in your browser — no location ever leaves your device, and selections live only in the URL. The basemap uses MapLibre GL JS with OpenFreeMap vector tiles (OpenStreetMap data), GPU-rendered.

💡 Use Cases

  • Emergency services: say "I'm at ocean,zebra,apple" instead of reading out long coordinates.
  • Logistics & delivery: define zones and reference addresses without street names.
  • Remote & rural areas: share hiking spots or coordinate rescues where there are no addresses.
  • Privacy: reference a place without revealing an exact street address, independent of any centralized service.
  • Research: standardized identifiers for field sites and observations.

❓ FAQ

How is BGrid different from other word-based systems?

BGrid is hierarchical (levels nest within each other), open-source, supports numbers/words/DD, and its precision scales with the chosen level.

Can I use BGrid offline?

The coordinate math works offline; only the map tiles need a connection. You can self-host with cached tiles for fully offline use.

Why 2048 divisions per level?

2048 = 211, efficient for computation and matching the BIP39 wordlist exactly.

Do parcels respect borders or coastlines?

No — they are purely mathematical divisions of the surface, independent of political or physical features.

Is there an API?

BGrid runs client-side without a central API; the algorithm is open-source on GitHub.