Grid Marks FAQ
The questions surveyors actually ask before they trust a tool with a day's work — what it costs, where the data lives, and what happens when the signal goes. Including the limits, because finding those on site is worse than reading them here.
Cost and accounts
Is Grid Marks really free?
Yes. No login, no paywall, no trial period, and nothing in the app is locked today. It is built with no server and no database, which means it costs almost nothing to run and there is no per-user cost to recover. Keeping it free is a constraint the app is designed around, not an introductory offer.
If a paid tier ever appears it would be aimed at heavier team workflows. Nothing that works today is planned to move behind it.
Do I need an account?
No. There is no sign-up, no email address, no password. Open gridmarks.co.uk and start working — that is the whole onboarding.
Is there advertising or tracking?
No advertising. Analytics are cookieless by default: they count visits and referrers, with no personal data and no profile of you. Anything cookie-based stays off unless you opt in. See the privacy policy.
Do I have to install anything?
No. It runs in any modern browser. You can add it to your phone's home screen so it opens full screen like an app — worth doing, for the storage reason below — but that is a browser feature, not an install.
Your data
Where is my data stored?
On your device, in your browser's own storage. Grid Marks has no backend and no database — there is no server holding your job list, so it cannot be read by us, leaked from us, or handed to anyone who asks us.
The honest trade-off: nothing is backed up for you. Export a project file if the work matters.
What happens if I clear my browser data?
Your marks go with it, because that is the only place they lived. Clearing site data, private browsing, or moving to a different browser or computer all start you empty.
Two things protect you: export a project file before you clear anything, and add the app to your home screen, which makes browsers far less likely to evict your storage after a spell of not using it.
Can I move my work to another device?
Yes — export a project file and open it on the other device. There is no cloud sync, which is the direct consequence of there being no account and no server.
Is it GDPR-safe to put client sites in it?
Nothing you enter is transmitted to us, which removes the usual processor relationship entirely. Address lookup and routing do send coordinates to third-party services when you use those features and are online. Your own obligations to your clients are still yours — this is not legal advice.
Working offline
Does it really work with no signal?
Yes, provided you downloaded the area first. Over wifi, open Offline maps and download the council areas you will be working in. On site with no signal, the app opens, your marks are there, and the street map renders from the device.
What does not work offline: satellite imagery, address search, and reverse-geocoded addresses for new pins. Those need a connection by definition.
How much space does an offline area take?
It varies by council — small urban authorities are a couple of megabytes, large rural ones considerably more. The picker shows the size before you download and a running total of what you have stored, so you can see the cost before committing to it.
Why can't I save the street map for an area directly?
The online street map is served by OpenStreetMap, whose fair-use policy allows caching tiles as you view them but not bulk downloading. Rather than quietly breach that, Grid Marks points you at the proper route: download a council area under Offline maps for offline street coverage. Satellite areas can still be saved as an image patch.
Getting your jobs in
What can I import?
Excel (.xlsx, .xls) and CSV. You match your
spreadsheet's columns to name, coordinates, due date, category and notes —
no template to conform to, because your job list already exists in whatever
shape it exists.
Mixed coordinate formats in one file are handled per row, so a spreadsheet with grid references on some lines and easting/northing on others imports in one pass. Full walkthrough.
What coordinate formats are supported?
OS grid references (for example NS 5642 6518), British National
Grid easting and northing, latitude and longitude, UK postcodes, what3words,
and your device's GPS position.
Grid reference guide.
How accurate are the coordinates?
Metre-level, not survey-grade. Conversion between OSGB36 British National Grid and WGS84 uses a Helmert transformation, accurate to a few metres.
That is right for finding a site, planning a route and marking a position. It is not a substitute for a survey-grade transformation such as OSTN15 in anything you deliver to a client. We would rather tell you that than have you discover it in a deliverable.
On site
Can I plan the order of a day's visits?
Yes. Plan day orders the selected marks into a sensible driving route, with distances and drive times, and draws it on the map. You can export the plan or print it.
Can I check the land registry from a site?
Yes — a pin opens public land register search for Scotland (ScotLIS), England and Wales, and Northern Ireland. These are free public services; Grid Marks links to them rather than reselling their data.
Can I check for buried services?
There is an LSBUD button on Great Britain pins. It copies the easting and northing and opens LSBUD so you can run a coordinate search in their free service. Northern Ireland is not covered by LSBUD.
It is a shortcut to their enquiry form — not a substitute for making the enquiry, and not a live plant record.
How do I mark due dates so they stand out?
Give a mark a due date and its pin is coded by both colour and shape — overdue, today, this week, later. The shape matters: colour alone fails for colour-blind users and in bright sunlight on a phone screen.
Something not answered here? Email hello@gridmarks.co.uk. Questions from people doing the actual work are how this list gets better.