Spying myself through the lense of Google Maps Timeline data

I took an export of my Google Maps Timeline data and discovered it to be a treasure trove of information. I was initially only interested in seeing how often I visit the local boulder gym, but I found myself soon digging into more such details.

The data consist of activities and place visits. An activity looks like this:

	{
	"activitySegment": {
	"startLocation": {
	"latitudeE7": 0,
	"longitudeE7": 0,
	"sourceInfo": {
	"deviceTag": -0
	}
	},
	"endLocation": {
	"latitudeE7": 0,
	"longitudeE7": 0,
	"sourceInfo": {
	"deviceTag": -0
	}
	},
	"duration": {
	"startTimestamp": "2023-02-01T03:49:39.393Z",
	"endTimestamp": "2023-02-01T03:57:21.480Z"
	},
	"distance": 1110,
	"activityType": "CYCLING",
	"confidence": "HIGH",
	"activities": [
	{
	"activityType": "CYCLING",
	"probability": 89.22557234764099
	},
	{
	"activityType": "WALKING",
	"probability": 6.305336207151413
	},
	{
	"activityType": "IN_PASSENGER_VEHICLE",
	"probability": 1.5200317837297916
	},
	{
	"activityType": "IN_BUS",
	"probability": 1.4393270947039127
	},
	{
	"activityType": "IN_SUBWAY",
	"probability": 0.44777640141546726
	},
	{
	"activityType": "MOTORCYCLING",
	"probability": 0.3105701180174947
	},
	{
	"activityType": "RUNNING",
	"probability": 0.2760248025879264
	},
	{
	"activityType": "IN_TRAIN",
	"probability": 0.17639625584706664
	},
	{
	"activityType": "IN_TRAM",
	"probability": 0.15619536861777306
	},
	{
	"activityType": "STILL",
	"probability": 0.1334176049567759
	},
	{
	"activityType": "IN_FERRY",
	"probability": 0.0047270386858144775
	},
	{
	"activityType": "SKIING",
	"probability": 0.003990190816693939
	},
	{
	"activityType": "SAILING",
	"probability": 6.135768217063742e-4
	},
	{
	"activityType": "FLYING",
	"probability": 1.9939299988891435e-5
	},
	{
	"activityType": "IN_VEHICLE",
	"probability": 2.1501850647198673e-9
	}
	],
	"waypointPath": {
	"waypoints": [
	{
	"latE7": 0,
	"lngE7": 0
	},
	{
	"latE7": 0,
	"lngE7": 0
	},
	{
	"latE7": 0,
	"lngE7": 0
	}
	],
	"source": "INFERRED",
	"roadSegment": [
	{
	"placeId": "someid",
	"duration": "31s"
	},
	{
	"placeId": "someid",
	"duration": "16s"
	},
	{
	"placeId": "someid",
	"duration": "38s"
	},
	{
	"placeId": "someid",
	"duration": "28s"
	},
	{
	"placeId": "someid",
	"duration": "91s"
	}
	],
	"distanceMeters": 1480.0706767917454,
	"travelMode": "BICYCLE",
	"confidence": 0.0
	}
	}
	}

view raw timelineactivity.json hosted with ❤ by GitHub

You can peek through the internals in a way since you can see which options for a given activity Google algorithms have considered.

A place visit, on the other hand, is:

	{
	"placeVisit": {
	"location": {
	"latitudeE7": 0,
	"longitudeE7": 0,
	"placeId": "ChIJC8gdEfd2jEYR-_H0G00KSq4",
	"address": "Aninkaistenkatu, 20100 Turku, Suomi",
	"name": "Linja-autoasema",
	"semanticType": "TYPE_SEARCHED_ADDRESS",
	"sourceInfo": {
	"deviceTag": -0
	},
	"locationConfidence": 57.1172,
	"calibratedProbability": 48.786476
	},
	"duration": {
	"startTimestamp": "2023-01-01T03:37:21.480Z",
	"endTimestamp": "2023-01-01T04:56:24.466Z"
	},
	"placeConfidence": "MEDIUM_CONFIDENCE",
	"centerLatE7": 0,
	"centerLngE7": 0,
	"visitConfidence": 96,
	"otherCandidateLocations": [{
	"latitudeE7": 604571641,
	"longitudeE7": 222681737,
	"placeId": "ChIJc9Dc5Ph3jEYR8pWWIcfi0r4",
	"address": "Läntinen Pitkäkatu 7, 20100 Turku, Suomi",
	"name": "Turku Bus Station",
	"locationConfidence": 13.238819,
	"calibratedProbability": 11.307895
	}, {
	"latitudeE7": 604567433,
	"longitudeE7": 222656352,
	"placeId": "ChIJH7NECvd2jEYRH4YOsng8Ofw",
	"address": "20100 Turku, Suomi",
	"name": "Turku bus station",
	"locationConfidence": 10.178642,
	"calibratedProbability": 8.694055
	}, {
	"latitudeE7": 604564020,
	"longitudeE7": 222666501,
	"placeId": "ChIJPVBncfd2jEYRLLPS3XEXJ1I",
	"address": "20100 Turku, Suomi",
	"name": "Turku, bus station",
	"locationConfidence": 9.436044,
	"calibratedProbability": 8.059767
	}],
	"editConfirmationStatus": "NOT_CONFIRMED",
	"locationConfidence": 46,
	"placeVisitType": "SINGLE_PLACE",
	"placeVisitImportance": "MAIN"
	}
	}

view raw placevisit.json hosted with ❤ by GitHub

As you can see, the data contains not just the place you can see from Maps you have visited but actually the metadata and the confidence scores of where Google thinks you have been.

Using the dataset, it is pretty easy to find out which locations you have visited and how long you have stayed. I co-authored with ChatGPT this simple script that outputs how many hours and times you have visited a given place.

	import fs from 'fs'
	import path from 'path';
	// https://stackoverflow.com/questions/19700283/how-to-convert-time-in-milliseconds-to-hours-min-sec-format-in-javascript
	function parseMillisecondsIntoReadableTime(milliseconds){
	//Get hours from milliseconds
	var hours = milliseconds / (1000*60*60);
	var absoluteHours = Math.floor(hours);
	var h = absoluteHours > 9 ? absoluteHours : '0' + absoluteHours;
	//Get remainder from hours and convert to minutes
	var minutes = (hours - absoluteHours) * 60;
	var absoluteMinutes = Math.floor(minutes);
	var m = absoluteMinutes > 9 ? absoluteMinutes : '0' + absoluteMinutes;
	//Get remainder from minutes and convert to seconds
	var seconds = (minutes - absoluteMinutes) * 60;
	var absoluteSeconds = Math.floor(seconds);
	var s = absoluteSeconds > 9 ? absoluteSeconds : '0' + absoluteSeconds;
	return h + ':' + m + ':' + s;
	}
	let visits = 0;
	let timeSpentMs = 0;
	const placeNamePatterns = ['Interesting place', 'Interesting place with another name']
	const dataDirPath = './data';
	const yearsDirs = fs.readdirSync(dataDirPath);
	yearsDirs.forEach((yearDir) => {
	if (yearDir.length !== 4) {
	return;
	}
	let visitsYear = 0;
	let timeSpentYearMs = 0;
	const yearDirPath = path.join(dataDirPath, yearDir);
	const filesInYearDir = fs.readdirSync(yearDirPath);
	filesInYearDir.forEach((filename) => {
	const filePath = path.join(yearDirPath, filename);
	const data = fs.readFileSync(filePath, 'utf8');
	const timelineObjects = JSON.parse(data).timelineObjects;
	for (const timelineObject of timelineObjects) {
	if (timelineObject.placeVisit) {
	const placeVisit = timelineObject.placeVisit.location.name;
	const otherCandidateLocations = timelineObject.placeVisit.otherCandidateLocations;
	if (placeNamePatterns.some((pattern) => placeVisit?.includes(pattern)) || otherCandidateLocations?.some((location) => placeNamePatterns.some((pattern) => location.name?.includes(pattern)))) {
	const duration = timelineObject.placeVisit.duration;
	const start = new Date(duration.startTimestamp);
	const end = new Date(duration.endTimestamp);
	timeSpentYearMs = timeSpentYearMs + (end - start);
	visitsYear++;
	}
	}
	}
	});
	visits = visits + visitsYear;
	timeSpentMs = timeSpentMs + timeSpentYearMs;
	if (visitsYear === 0) {
	console.log(yearDir, 'no visits')
	console.log('\n')
	return;
	}
	console.log(yearDir)
	console.log(visitsYear, 'visits')
	console.log(parseMillisecondsIntoReadableTime(timeSpentYearMs), 'time spent')
	const average = timeSpentYearMs / visitsYear;
	console.log(parseMillisecondsIntoReadableTime(average), 'average time spent per visit')
	console.log('\n')
	});
	console.log('Total')
	console.log(visits, 'visits')
	console.log(parseMillisecondsIntoReadableTime(timeSpentMs), 'time spent')

view raw timelinespy.js hosted with ❤ by GitHub