Why Google Maps, Apple Maps, Waze and TomTom disagree on ETAs

Four navigation apps can give four different arrival times for one drive, and usually none of them is broken: they are answering slightly different questions. Below are the six causes that matter most, what Mapssy learned while putting the apps side by side, and a short routine for comparing them fairly.

The six causes at a glance

1. Each app puts your destination somewhere different

Type a town such as Graz and each app first turns the name into a single point: the centre, the town hall, a main square or a particular street. For an airport, a shopping centre or a castle, the route must also end at some road or entrance, and the apps do not always pick the same one. A few hundred metres at the end of a trip can mean a different motorway exit or a loop through a one-way town centre.

Mapssy's own comparison had this fault. Early versions timed every trip to TomTom's point for the place but sent the place name to Google Maps and Apple Maps, which then routed to spots of their own choosing, so the figures no longer described the same trip. Now the Google Maps, Waze and TomTom buttons open the place their figure was timed to; on the website the Apple Maps figure is a Mapssy estimate, and its button lets Apple Maps place the name itself. The full story is in Same name, different place.

2. Each app sees traffic through its own data

Live traffic is not one shared feed. Each company measures speeds with its own sources, which it describes on its own pages:

Because the samples differ, two apps can spot the same slowdown at different moments or judge it differently. Google adds that live data cannot show what a road will look like by the time you reach it, so it blends live and historical traffic using machine learning. TomTom refreshes its traffic picture every 30 seconds.

3. Your settings change the route

Two people using the same app can get different answers because of a setting one of them has forgotten about:

• Fuel-efficient routes (Google Maps). Google offers this only in select countries or regions, and announced it for nearly 40 European countries in 2022. With Prefer fuel-efficient routes on, Google Maps recommends the most efficient route when its arrival time is roughly the same as the fastest one, and the engine type you choose can change which route that is.
• Avoid tolls, motorways or ferries. Google Maps and Apple Maps let you avoid tolls and motorways (highways), Waze can avoid toll roads, ferries and freeways, and TomTom's routing service can avoid toll roads, motorways, ferries, tunnels, unpaved roads and more. Waze warns that it may still suggest toll roads with the option on. If one app avoids what another allows, you are comparing different roads.
• Vignettes (Waze). Waze lets you add the road passes and vignettes you hold and says it guides you based on them. Where motorways need a vignette, as in Austria, Slovakia, Czechia and Hungary, check which roads each app chose; prices are in Motorway vignettes 2026.
• Personalised estimates (Waze). Waze can learn from your past drives how long you take on each road segment, and says this is on by default where it is supported.
• Route type (TomTom). TomTom's routing service can return the fastest, shortest, eco or 'thrilling' route for the same trip, each with its own time, so a TomTom-based planner set to anything but fastest will quote a different figure.

4. The minute you ask matters

An estimate is a snapshot of the moment it was calculated. Checking one app before you leave and another a quarter of an hour later compares two moments of the same rush hour. Estimates keep moving on the road too: Google says Google Maps reroutes automatically when it expects a jam ahead, and Waze says its ETA accounts for traffic conditions and irregular events such as accidents.

Setting a departure time is a different question again. Google Maps then finds the best route based on estimated traffic, and Apple says the estimated travel time may change based on predicted traffic. TomTom's routing service also accepts a departure time, and its documentation says it can take planned closures and roadworks into account up to 60 days ahead, where they are known.

5. Each app assumes its own speeds

No app simply divides the distance by the speed limit. Waze uses the average speed its users drive. TomTom uses historical speed profiles, which its documentation says still apply when live traffic is switched off. Google blends historical and live traffic and takes speed limits from sources such as local governments. TomTom also notes that legal limits can depend on the time of day and on the vehicle.

That matters where the limits vary. Austria allows 130 km/h on motorways but 110 km/h from 22:00 to 05:00 on the Tauern motorway and some other routes, plus IG-L air-quality limits, usually 100 km/h, including permanent ones on parts of the A12 and A13 in Tyrol. On the Czech D3 between kilometres 84 and 131, variable signs allow 150 km/h in a pilot extended to the end of 2026; the transport ministry's own figures show that mode was active 39% of the time from October 2025 to March 2026. Germany has no general motorway limit, only a recommended 130 km/h.

The effect adds up quickly. Over 100 km, 130 km/h takes about 46 minutes and 110 km/h about 54½ minutes: a gap of more than 8 minutes from the speed assumption alone, before any traffic.

Your vehicle counts too. Waze says it was created for private cars, motorcycles and taxis, whereas TomTom's routing service accepts a truck mode (van and bus modes are in beta) and a maximum vehicle speed. If a lower limit applies to you, for example when towing, a car estimate will tend to be optimistic.

6. Incidents reach each app differently

A crash or a closed lane changes an arrival time only once the app knows about it:

• Waze drivers report traffic, accidents, police, blocked roads and weather, and Waze uses those reports to route other drivers.
• Google Maps uses drivers' reports of closed roads or lanes, construction and broken-down vehicles, alongside data from local governments.
• Apple Maps shows reported accidents and hazards to other users only when Apple has high confidence in the reports.
• TomTom detects congestion in its probe data and takes closures and roadworks from government and other trusted sources and from TomTom device users; its moderation teams validate critical local road reports.

So just after a crash, one app may already be routing around it while another still shows a clear road.

What Mapssy learned from the side-by-side view

Even one provider answers differently depending on how it is asked. Google's Routes API ignores live traffic by default, and its second, traffic-aware mode answers faster but not at the highest quality; Mapssy uses the third mode, which Google documents as equivalent to the Google Maps app. And two of the four are not asked on the website: Waze has no public routing service, and Apple's web services (MapKit JS and the Apple Maps Server API) answer only requests signed with an Apple developer key, which the Mapssy website doesn't use. For those two, Mapssy calculates a figure from Google's and TomTom's live answers and marks it estimate; the Mapssy iPhone app asks Apple directly. A button opens each app so you can see its own number. How Mapssy works has the details.

How to compare arrival times fairly

1. Ask at the same minute. Mapssy's route planner asks Google's and TomTom's routing services at the same moment and shows the time it checked them.
2. Check the destination pin in each app, especially for towns, airports and large sites.
3. Match the settings in every app you compare; the settings guide covers each app.
4. Compare the route and distance, not only the time. A gap of several minutes often means different roads, such as the two corridors in Vienna to Prague by car.
5. Treat small gaps as noise. On a long drive, a difference of a few minutes can appear or vanish as traffic changes.
6. Watch the estimate update in the app you drive with once you set off.