If your Google Maps export has no coordinates, check which file you downloaded. A CSV from Takeout's Saved export usually doesn't include them. You'll need another source to get those numbers.
If the file does have coordinates but the pins land in the wrong place, check a few entries before changing anything. Two zeros, a reversed pair of numbers, and an old address each need a different fix.
The CSV has names and links, but no coordinates
Open the CSV and look at the column headings. If there's no latitude or longitude column, converting it to GeoJSON won't add the missing locations.
For Starred places, try Google Takeout's Maps (your places) export. Look for Saved Places.json, which can contain coordinates. You can open it with the Takeout Import page.
For a custom or shared list, open the list in Maps and export it with the Chrome extension. It can read coordinates from the places in the list.
The similar Takeout names are easy to mix up. The Saved Places.json vs Saved CSV guide shows what each file contains.
Why a place shows up at [0,0]
[0,0] means zero longitude and zero latitude. That's a point in the sea off West Africa. If your saved café appears there, the file has the wrong coordinates for it.
Check entries where both numbers are zero. They may be written as [0,0], [0, 0], or [0.0, 0.0]. One zero on its own can be correct: real places sit on the equator or the prime meridian.
Keep the place's name, notes, and Maps link. You'll need those to find it again. Try exporting the list once more, or copy the correct coordinates from the map using the steps below.
The numbers are there, but the order is wrong
Google Maps gives you latitude, longitude when you copy coordinates. GeoJSON needs longitude, latitude], as defined in the [GeoJSON specification.
For example, a point in central Berlin is about 52.52 latitude and 13.405 longitude. In GeoJSON, write [13.405, 52.52]. Reverse those numbers and the pin ends up thousands of kilometres away.
Check a place you know before swapping whole columns. Latitude must be between -90 and 90; longitude between -180 and 180. Both Berlin numbers fit either range, so checking the ranges alone won't catch this mistake.
Some places don't appear on the map
An entry can have a name and notes but no location. In GeoJSON, "geometry": null means there's no shape or point to draw. It is allowed in the format, even though the place won't appear on a map.
The GeoJSON validator can read the file and report how many places it contains and the area they cover. It doesn't check every coordinate or tell whether a pin belongs to the right café. Even [0,0] can pass a format check.
ExportMyMap can leave places without usable coordinates out of KML, GPX, and GeoJSON exports. If you selected 50 places and got 48 points, check the two missing entries in the source list.
The pin is on the wrong street
Open the original Maps link and compare the name and full address. A business may have moved, or an address lookup may have found a different branch with the same name. The website or phone number can help tell them apart.
Avoid copying numbers straight from the browser's address bar. Some Maps URLs contain the centre of the map you're viewing, which may be different from the place's pin.
How to fix the affected places
1. Save a copy of the file
Keep the original and edit a copy. That way, you'll still have the old links and notes if you need them.
2. Make a short list of what is wrong
Write down which places are missing or misplaced. Check the whole map too: if most pins are wrong, start with the coordinate order.
3. Try exporting the list again
If the list still opens in Maps, make a new GeoJSON export. Check the affected places in that file. A fresh export may save you some manual work, though it won't help if the source listing is wrong too.
4. Copy coordinates for any places still missing
On a computer, find the place in Maps and confirm its address. Right-click the exact location on the map, then click the coordinates at the top of the menu to copy them.
The copied pair is latitude, longitude. Put each number in its matching spreadsheet column. For a GeoJSON point, reverse the pair to [longitude, latitude]. Keep a note of which rows you changed.
5. Open the edited file on a map
Check the file with the validator after editing. Then compare the place count and look at every pin you changed. In QGIS, Zoom to Layer shows all the points at once; the QGIS guide covers the import steps.
Still can't find a place?
Keep it in a separate sheet with its name, link, and notes. Leave the coordinates blank until you can confirm the location.
Once you've checked the places, save them as CSV for a spreadsheet, GPX for waypoints, or GeoJSON for a mapping app.