Blog
Guides and use cases for grid overlays, distance measurement, and spatial planning.
Start with a guide
Map Grid References
MGRS, UTM, and custom grids, how to read a grid square, and how to overlay one on any map.
GPX and KML
Open, edit, and convert GPX and KML files, measure distances, and export to PDF or GeoJSON.
All articles
Corner Crossing, a Ladder, and a BLM Map
September 10, 2026
Four Missouri hunters, one stepladder, a seven-figure lawsuit and a checkerboard of public land the railroads left behind. The Wyoming corner crossing case, told the fun way, and how to find the corner on a map before you leave the driveway.
Read article →Share a Map With a Read-Only Link
September 5, 2026
A screenshot is a picture of a decision. A link is the map. Send a saved map to a team leader, a class, or whoever is waiting at home, and they open the grid, the routes and the symbols in a browser with no account. Read-only, good for 30 days, and you can stop it whenever you want.
Read article →Open and Edit a Geospatial PDF (GeoPDF) Online
September 1, 2026
Every other way to open a GeoPDF is an installed app. Import one here and it lands georeferenced on a live basemap in the browser: pick the page, toggle the file's own layers, trim the collar, then grid it, draw on it, and export it back out.
Read article →Export a Geospatial PDF (GeoPDF) Online
August 31, 2026
Prepare the map here, take it to your favorite app. Build the grid, the route and the symbols in the browser, export one geospatial PDF, and open it in your offline map app. Your GPS position rides on your own map, with no signal required.
Read article →How to Divide a Search Area into Sectors
August 15, 2026
Draw the search area on a live map, split it into up to 1,000 lettered squares, and paint each team's share in its own color. Copy the roster for the ICS-204, then export a true-scale PDF, an image, or GeoJSON for the county GIS. About a minute in the browser, no desktop GIS.
Read article →MapGridder for SAR Teams: An Overview
August 9, 2026
The map work of a search in a browser tab: 65 NAPSG-standard symbols, a USNG grid under everything, containment rings around the LKP, last light and radar for the night shift, and team tracks laid over segments at debrief. What the subscription platforms charge for, minus the platform.
Read article →A GeoTIFF Map Editor That Runs Online and Keeps Your Imagery Private
August 4, 2026
Open a georeferenced raster straight on the map: it places itself from the georeferencing inside the file, your MGRS or metric grid renders over it, and the pixels are read on your device instead of uploaded. For operators, milsim organizers, and analysts who would rather not install desktop GIS.
Read article →Weather Planning on a Map: Hiking, Tactical, Navigation
July 20, 2026
Everybody has a weather app; the plan lives on a different map. Put live radar, a 48 hour rain forecast, and cloud cover under your MGRS grid, GPX routes, and tactical symbols, tap for the intensity at any point, and pick the departure window that keeps the route dry.
Read article →What Is a Plus Code and How to Read One
July 14, 2026
Plus Codes like 8FVC9G8F+6X give any spot on Earth an address with one repeated rule: divide the world 20 by 20 and name the cell. Learn how the pairs work, what short codes like 9G8F+6X Zurich mean, and how the grid compares to MGRS.
Read article →What Is GARS and How It Differs from MGRS
July 13, 2026
GARS names areas, MGRS names points. Learn how the Global Area Reference System's 30-minute cells, quadrants, and keypads work, how to read a reference like 380MK17, and when each system is the right tool.
Read article →Elevation Profiles for GPX Routes and Hikes
July 12, 2026
Draw or import a GPX route and watch its elevation profile build right in the route panel, gain, loss, and a trace dot that follows your cursor along the trail. Plus a two-click Height Profile tool for checking the terrain between any two points. Written from the perspective of someone who has regretted a few climbs.
Read article →What Is the Maidenhead Grid and How to Read It
July 9, 2026
Maidenhead locators like JN58td pack a location into a few characters. Learn how the field, square, and subsquare pairs work, how to read one on a map, and how the grid compares to MGRS and lat/long.
Read article →How to Find Sunrise, Sunset, and Moon Times on a Map (and What Twilight Means)
July 7, 2026
Find sunrise, sunset, moonrise, and moonset for any location and date, then read the sun and moon angles, shadows, and twilight on the map. Includes a plain-language guide to civil, nautical, and astronomical twilight, and what BMNT and EENT mean.
Read article →MGRS vs UTM vs Lat/Long: The Difference, Explained
Updated July 2, 2026
MGRS, UTM, and latitude/longitude describe the same point three different ways. A side-by-side comparison with one real location written in all three, when to use each, and how to overlay all three as live map grids.
Read article →Free MGRS Grid Overlay: NATO-standard grid on any map
Updated July 2, 2026
MapGridder supports MGRS, the NATO-standard worldwide geocoordinate grid, plus plain UTM and lat/long graticule overlays. Useful for OSINT analysts, navigation hobbyists, geocachers, and map enthusiasts. Free for non-commercial use, no login, with the coordinate math running entirely in your browser.
Read article →How to Create a GRG: Overlay an Image and Add a Grid
June 12, 2026
Drop a reference image (a map scan, building diagram, or aerial photo) onto an interactive map, georeference it by eye in Simple or Pro mode, then add a metric or MGRS grid on top. A free, in-browser way to build a gridded reference graphic with no login.
Read article →How to Export a Map to GeoJSON (Free, In Your Browser)
June 10, 2026
Save your waypoints, routes, measurements, shapes, symbols, and grid lines as a standard GeoJSON FeatureCollection. One file that almost every mapping and GIS tool can open, built entirely in your browser with nothing uploaded; a quick, free sign-in is only needed to export.
Read article →How to Read a Military Grid Reference (6, 8, and 10-Figure)
June 4, 2026
The grid zone, the 100,000 meter square, and the easting and northing digits, with the 'read right, then up' rule and worked 6, 8, and 10-figure examples on a real location.
Read article →What Is GeoJSON? Format, Structure, and Every Geometry Type
June 1, 2026
A technical explainer of the GeoJSON format (RFC 7946): the FeatureCollection / Feature / Geometry structure, longitude-first coordinate order, all seven geometry types, the bbox member, and the gotchas that trip people up. With real JSON examples.
Read article →How to Export a Map as PDF at Real Scale, with MGRS Grid and Annotations
May 10, 2026
A step-by-step guide to exporting your map as a high-resolution image or as a paper-sized PDF (A4, A3, Letter) at a real cartographic ratio (1:10,000 to 1:1,000,000), with the MGRS grid, annotations, and waypoints baked in.
Read article →Edit GPX Files Online: View, Annotate & Export Tracks
March 14, 2026
Import a GPX file from Strava, Garmin, or AllTrails. View the track, annotate the route, overlay a reference grid, and export a clean screenshot. No software to install; a quick, free sign-in is only needed to export.
Read article →Free Map Grid Tool: No Watermark, No Fees
March 9, 2026
Most online map tools watermark exports, charge fees, or force sign-up. Here is why free tools are so rare, and how MapGridder breaks the pattern.
Read article →Grid Referencing for Beginners: How Row-Column Labels Work
March 9, 2026
Understand how grid references like "B3" or "D7" let teams communicate positions on a map without GPS coordinates.
Read article →How to Measure Distances on a Map Without GIS Software
March 9, 2026
A quick guide to using browser-based tools for straight-line and multi-point distance measurement on interactive maps.
Read article →6 Ways to Use a Grid Overlay on Maps for Better Planning
March 8, 2026
From event layouts to volunteer field coordination, learn how a simple metric grid (combined with annotations and waypoints) transforms spatial planning.
Read article →