About

Covering 416 cities across 57 countries on 6 continents, our Traffic Index ranks urban congestion worldwide and provides free access to city-by-city information. You, along with drivers, city planners, automakers and policy makers, can use the index to help tackle traffic-related challenges. Now in its 9th year, you’ll find even more insights from both real-time and historical data.

The TomTom Traffic Index is one more way we are helping create a safer, cleaner, congestion-free world, together with our partners and global community of drivers.

Our methodology

The numbers

Wondering how we determine the rankings, and what exactly the percentages mean?

A 53% congestion level in Bangkok, for example, means that a 30-minute trip will take 53% more time than it would during Bangkok’s baseline uncongested conditions.

You can turn this 53% into travel time through simple calculations.
First: 0.53 x 30 mins = 15.9 mins extra average travel time.
Second: 30 mins + 15.9 mins = 45.9 mins total average travel time.

We calculate the baseline per city by analyzing free-flow travel times of all vehicles on the entire road network – recorded 24/7, 365 days a year. This information allows us to also calculate, for example, how much extra time a driver will spend in traffic during rush hour in Bangkok.

We perform calculations for all hours of each day, so you can see congestion levels at any time in any city, including morning and evening peak hours.

The data

With TomTom, your data is never sold and is always anonymized – meaning we break the link between your identity and the data we receive. Our Traffic Index data comes from our growing community of more than 600 million drivers, who use TomTom tech in navigation devices, in-dash systems and smartphones around the world.

The colors

The color-coded figures you see are based on measurements from TomTom's historical traffic database. To ensure our statistics best represent the driving experience on the road, we measure individual road segments as well as entire road networks. Then we weight busier, more important roads to calculate an accurate overall congestion level.

You’ll see four different colors indicating congestion levels in cities.

> 50%
25% - 50%
15% - 25%
< 15%

Definitions

DATA COVERAGE
Refers to the total kilometers/miles of GPS data from actual driven trips used to calculate our statistics per city. Data coverage is reported separately for highways and non-highways.
EXTRA TRAVEL TIME PER DAY
Extra travel time during peak hours compared to a one-hour period during free flow conditions.
EXTRA TRAVEL TIME PER YEAR
Extra travel time during peak hours as compared to a one-hour period during free flow conditions, multiplied by 230 working days per year.
MORNING/EVENING RUSH
The busiest one-hour period in the morning/evening as defined per city based on actual traffic measurements.
FREE FLOW
A traffic situation in which travel times are not impacted by congestion. Typically occurs at night but can happen any time of day.
CONGESTION LEVEL BY TIME OF DAY
This table shows the congestion level for each hour of each day of the week, on average across the entire year, for each city.
DAY WITH LOW TRAFFIC
Day with the congestion level that is at least 50% lower than the congestion level on the corresponding day in the previous year.
TOTAL ROAD NETWORK LENGTH
Total length of evaluated road system.
Urban area boundaries
We defined our own urban areas, using the same methodology for all cities indexed around the world. We did it ourselves to increase accuracy, as municipal and statistical boundaries are not internationally uniform in their size and coverage of urban areas.
CONGESTION LEVEL NOW

The current extra travel time drivers are experiencing on average. It is calculated using TomTom’s real-time traffic information, as opposed to our historical data used elsewhere throughout the Traffic Index.

TRAFFIC JAMS NOW

The current number of traffic jams (and their total length), based on TomTom’s real-time traffic information.