what3words is a global grid system that labels every 3m × 3m square on earth with three ordinary words. "filled.count.soap" is a specific square near the River Trent. It's precise enough to identify a fishing peg or a roost tree, short enough to type on a phone, and impossible to get wrong through a typo (unlike coordinates).
Coordinates work — but they're awkward in practice:
- Long and hard to type.
52.93816, -1.17732is 15 characters including symbols. One transposed digit and you're a kilometre off. - No error-checking. If you mis-type a coordinate, there's no way to know you did.
- Hard to share. Try reading coordinates aloud to someone else. Try remembering them.
- Precision varies. Five decimal places is about a metre. Four is ten metres. Three is a hundred. Most people don't know which they're copying.
what3words fixes all of this:
- Three words, always. Any location on earth is three ordinary words.
- Error-resistant. If you mistype, the words still form valid addresses, but they'll point somewhere far away — so it's obvious something's wrong.
- Easy to share. "My sighting was at filled.count.soap" reads fine over the phone, in a text message, in field notes.
- Fixed precision. Every what3words address is exactly 3m × 3m. No ambiguity.
A cormorant sighting "near the river" is not evidence. A cormorant sighting at a specific 3m × 3m square, at a specific date and time, photographed, is evidence.
Same for biodiversity — "I saw a kingfisher somewhere on this stretch" is a nice memory. "I saw a kingfisher at filled.count.soap on Saturday at 07:42" is a data point. Multiply that across thousands of sightings and you have a dataset someone can do something with.
what3words is how we get precision without making people type coordinates.
Three ways:
1. Automatic (recommended)
- Tap the crosshair icon next to the what3words field on any form
- Your device GPS captures the current location
- The app converts it to what3words automatically
- You're done
This is the fastest route if you're at the location right now.
2. Manual
- Type the three-word address directly into the field (e.g.
filled.count.soap) - Use dots or slashes between words
- The app validates as you type — you'll see the location on the map
Useful if you know the what3words address from memory, from a note, or from another device.
3. From the what3words app or website
- Open what3words.com or the what3words app
- Find your location on the map (or capture GPS)
- Copy the three-word address
- Paste it into the Hydroscape form
Useful if you want to look up a location without opening Hydroscape first.
If you've already captured your coordinates via GPS, the app can't always convert them to words without a connection. In that case, you can:
- Submit with GPS coordinates only (the app accepts this)
- Or note the coordinates manually, convert them later when online, and submit the what3words retrospectively
Either way, precision isn't lost.
what3words precision is absolute (always 3m × 3m), but your device's GPS accuracy isn't. On a phone in open ground, GPS is typically accurate to 5–10m. Indoors, near tall buildings, or under heavy tree cover, it drops off. If you're in dense woodland or a steep valley, check the pin the app drops actually matches where you are — if it's clearly wrong, adjust manually.