# Speed limits in Japan

The highest speed limit in Japan is 120 km/h (approximately 74.6 mph), which applies on sections of Shin-Tōmei Expressway (E1A) and Tōhoku Expressway (E4), and expressways in the Kantō Plain leading to Tokyo, although a speed limit of 120 km/h is planned to be introduced on some more expressways.
Statutory speed limit defaults to 100 km/h (approximately 62.13712 mph) for national divided expressways or 70 km/h (43.5 mph) for undivided expressways, 30 km/h (approximately 18.64 mph) for undivided roads without center line (from September 1, 2026) and 60 km/h (approximately 37.3 mph) for any other roads (unless otherwise posted). Urban two-way streets are usually zoned at 40 km/h (24.855 mph) or less. However, the statutory speed limit for divided expressways is (since April 1, 2024) 90 km/h (56 mph) for a truck with GVWR over 8 t (17,640 lb) and a maximum load over 5 t (11,020 lb), and 80 km/h (49.71 mph) for motor vehicles with a trailer and three-wheelers (and before April 2024 also for trucks over 8 t). There are no separate urban or rural statutory limits. Urban and rural limits are set by zoning rather than statute.
Implementation of speed limits in Japan can be summarized as:
* regulatory speed limits of 30 km/h on residential streets and 40 km/h are common for urban two-lane roads.
* regulatory speed limit of 40 or 50 km/h is common in rural areas due to rugged mountainous terrain.
* variable speed limits are in effect on most national expressways.
* emergency vehicles are not exempt but have speed limit of 80 km/h on most roads and 100 km/h on divided national expressways, unless higher speed limit is posted. Police vehicles are exempt during speeding enforcement.

## Enforcement
### Speed camera

A threshold for speed cameras in Japan is set at a minimum of 39 km/h (24 mph) above the limit on an expressway and a minimum of 29 km/h (18 mph) above the limit on other streets, where drivers will face criminal charges instead of traffic infractions. This is due to legal precedents dating back to 1969 restricting police from filming an individual unless a criminal offence is immediately being committed.

### Police enforcement

Although there is no official tolerance for exceeding the speed limit, most drivers in Japan tend to drive over the speed limit on major roads. Police enforcement varies depending on the jurisdiction, officers, traffic flow and street types, but 19 km/h (12 mph) above the speed limit on an expressway and 14 km/h (8.7 mph) above the limit are generally tolerated on other streets.
In 2020, a total of 1,162,420 speeding tickets were issued across Japan, and only 199 tickets were issued for speeding between 0 and 14 km/h (0.0 and 8.7 mph) over the limit. Of the 199 tickets for speeding 0–14 km/h (0.0–8.7 mph) over the limit, Iwate Prefectural Police alone issued 166 tickets. For speeding between 15 and 19 km/h (9.3 and 11.8 mph) over the limit, Hokkaido, Aichi, Kyoto, Osaka and Fukuoka had the largest shares of tickets issued.
In contrast, Okinawa did not issue any tickets for speeding between 0 and 19 km/h (0 and 12 mph) over the limit. Tokyo Metropolitan Police issued a total of 68,693 speeding tickets, but gave out only seven tickets for speeding between 0 and 19 km/h (0 and 12 mph) over the limit. Some jurisdictions, such as Tokyo Metropolitan Police, release traffic enforcement locations on their websites.

## Speed limit guidelines

There is also a major distinction between surface streets (一般道路, ippan dōro) and expressways (高速道路, kōsoku dōro) in terms of speed limit regulations, with different criteria applied for each.
Although some surface streets such as viaducts, trunk and bypass roads are built to expressway standards, many are not legally classified as expressways and are typically distinguishable by the colour of direction signs: surface streets use blue direction signs while expressways use green signs.

### Surface streets

Speed limits for surface streets are set within ±10 km/h (6.2 mph) of the reference speed limit below. Reference speed limits do not apply to expressways.
A speed limit may not exceed 60 km/h for any streets with at-grade intersections or where pedestrians or cyclists are permitted. To exceed the 60 km/h threshold, the street must undergo costly grade separation to become a controlled-access highway.
Reference Speed Limit for Surface Streets :
| Class | Area | Travel Lanes | Divided | Pedestrian Volumes | 85th Percentile Speed | Reference Speed Limit | Factors affecting the Reference Speed Limit (Reason for deviating from 85th speed) |
| 1 | Urban | 2 lanes | - | High | 51.9 km/h | 40 km/h | Urban and high pedestrian volumes |
| 2 | Urban | 2 lanes | - | Low | 57.1 km/h | 50 km/h | Urban |
| 3 | Urban | 4+ lanes | Yes | High | 59.0 km/h | 50 km/h | Urban and high pedestrian volumes |
| 4 | Urban | 4+ lanes | Yes | Low | 64.1 km/h | 60 km/h | Urban |
| 5 | Urban | 4+ lanes | No | High | 58.7 km/h | 50 km/h | Urban, high pedestrian volumes, and undivided |
| 6 | Urban | 4+ lanes | No | Low | 63.9 km/h | 50 km/h | Urban and undivided |
| 7 | Rural | 2 lanes | - | High | 58.2 km/h | 50 km/h | High pedestrian volumes |
| 8 | Rural | 2 lanes | - | Low | 63.3 km/h | 60 km/h | Maximum speed set by police |
| 9 | Rural | 4+ lanes | Yes | High | 65.3 km/h | 60 km/h | Pedestrian |
| 10 | Rural | 4+ lanes | Yes | Low | 70.4 km/h | 60 km/h | Maximum speed set by police |
| 11 | Rural | 4+ lanes | No | High | 65.0 km/h | 50 km/h | High pedestrian volumes and undivided |
| 12 | Rural | 4+ lanes | No | Low | 70.1 km/h | 60 km/h | Undivided |
| | Residential Streets Narrow streets primarily used by local residents, often without a sidewalk, where the safety of pedestrians and cyclists should be warranted over travel speed of vehicles. Note: Not to set within ±10 km/h (6.2 mph) | Residential Streets Narrow streets primarily used by local residents, often without a sidewalk, where the safety of pedestrians and cyclists should be warranted over travel speed of vehicles. Note: Not to set within ±10 km/h (6.2 mph) | Residential Streets Narrow streets primarily used by local residents, often without a sidewalk, where the safety of pedestrians and cyclists should be warranted over travel speed of vehicles. Note: Not to set within ±10 km/h (6.2 mph) | Residential Streets Narrow streets primarily used by local residents, often without a sidewalk, where the safety of pedestrians and cyclists should be warranted over travel speed of vehicles. Note: Not to set within ±10 km/h (6.2 mph) | Residential Streets Narrow streets primarily used by local residents, often without a sidewalk, where the safety of pedestrians and cyclists should be warranted over travel speed of vehicles. Note: Not to set within ±10 km/h (6.2 mph) | 30 km/h (±0 km/h) | 20 km/h limit may be set on case-by-case basis for the following: Street has a higher percentage of vulnerable road users, such as seniors. School zones, but only where specifically needed. Strong requests from local residents. Street not designed for motorized vehicles but still permitted due to unavoidable circumstances. |
| | Roads Structure Emphasizing the Traffic Function of Automobiles Ordinary roads (excluding expressways and motorways) that satisfy the following conditions: Minimum design speed of 60 km/h No at-grade intersection Divided and has low crash rates Note: Not to set within ±10 km/h (6.2 mph) | Roads Structure Emphasizing the Traffic Function of Automobiles Ordinary roads (excluding expressways and motorways) that satisfy the following conditions: Minimum design speed of 60 km/h No at-grade intersection Divided and has low crash rates Note: Not to set within ±10 km/h (6.2 mph) | Roads Structure Emphasizing the Traffic Function of Automobiles Ordinary roads (excluding expressways and motorways) that satisfy the following conditions: Minimum design speed of 60 km/h No at-grade intersection Divided and has low crash rates Note: Not to set within ±10 km/h (6.2 mph) | Roads Structure Emphasizing the Traffic Function of Automobiles Ordinary roads (excluding expressways and motorways) that satisfy the following conditions: Minimum design speed of 60 km/h No at-grade intersection Divided and has low crash rates Note: Not to set within ±10 km/h (6.2 mph) | Roads Structure Emphasizing the Traffic Function of Automobiles Ordinary roads (excluding expressways and motorways) that satisfy the following conditions: Minimum design speed of 60 km/h No at-grade intersection Divided and has low crash rates Note: Not to set within ±10 km/h (6.2 mph) | 70 km/h or 80 km/h (±0 km/h) | For speed limits 70 km/h and above, the road should be closed to pedestrians, cyclists, and mopeds in principle. Note: This criterion only applies to ordinary roads and does not apply to expressways and motorways. See Speed limits in Japan#Expressways for expressway adaptation speeds. |
| Definitions Urban: DID (Densely Inhabited Districts), defined as at least two adjacent census districts with a population density of 4,000/km$^2$ and a combined population greater than 5,000. Rural: non-DID Divided: Road must be separated by solid physical structures such as raised curb or fence. Roads divided by raised pavement markers or delineator posts are classified as "undivided". High Pedestrian Volumes Urban: 701 people/12 hr Rural: 101 people/12 hr Low Pedestrian Volumes Urban: ≤ 700 people/12 hr Rural: ≤ 100 people/12 hr ||||||||

### Expressways

A speed limit can be set at maximum 120 km/h (approximately 74.6 mph) on a divided expressway, if it has low crash rates, both the lowest adaptation speed and design speed is 120 km/h and the length is 20 km (12 miles) or more; on an undivided expressway, the speed limit can be set at maximum 70 km/h (43.5 mph).
The speed limit is set with the lowest "structure compatible speed" (構造適合速度, kōzō tekigō sokudo) criteria below, that is based on design speed in some factors. Unlike surface streets, there is no range limit such as ±10 km/h. Therefore, the speed limit can be modified without limit as long as 100 km/h or lower, but the adaptation speed should be "respected".
Intercity expressways typically have higher speed limits, while urban expressways within major cities often have a speed limit of 60 km/h (37.3 mph) and two-lane expressways, typically in rural and remote areas, have 70 km/h (43.5 mph) for simplified division such as guide posts and 80 km/h (49.71 mph) with physical separation.
Most expressways outside of cities have active variable speed limit signs and maximum speeds are lowered according to road conditions such as congestions, accidents, constructions and severe weather. When the statutory speed limits are in effect on national expressways, variable speed limit signs are left blank to indicate that the statutory speed limit applies. Two sets of variable speed limit signs are installed when the regulatory speed limit exceeds the statutory speed limit, which is 100 km/h on national divided expressways or 80 km/h on other roads, to regulate the speed limit for motor vehicles with a trailer and three-wheelers (which always is 80 km/h).
Even some 4-lane expressways have 70 km/h speed limit. There is, however, no speed limit of 90 km/h, although it is allowed.
Curve Radius and Superelevation :
| Curve Radius (m) | Curve Radius (m) | Curve Radius (m) | Curve Radius (m) | Curve Radius (m) | Curve Radius (m) | Curve Radius (m) | Adaptation Speed | Design standard | Exceptional |
| Exceptional |||||||
| 0 - 1 | 1 - 2 | 2 - 3 | 3 - 4 | 4 - 5 | 5 - 6 | 6 - 7 | Adaptation Speed | Curve radius (m) | Curve radius (m) |
| 1134 | 1031 | 945 | 872 | 810 | 756 | 709 | 120 km/h | (710) | (570) |
| 716 | 656 | 606 | 562 | 525 | 492 | 463 | 100 km/h | (460) | (380) |
| 420 | 388 | 360 | 336 | 315 | 296 | 280 | 80 km/h | (280) | (230) |
| 218 | 202 | 189 | 177 | 167 | 157 | 149 | 60 km/h | (150) | (120) |
| 141 | 131 | 123 | 116 | 109 | 104 | 98 | 50 km/h | (100) | (80) |
| 84 | 79 | 74 | 70 | 66 | 63 | 60 | 40 km/h | (60) | (50) |
| 47 | 44 | 42 | 39 | 37 | 35 | 34 | 30 km/h | (30) | |
| 21 | 20 | 19 | 17 | 17 | 16 | 15 | 20 km/h | (15) | |
Sight Distance :
| Sight distance | Adaptation Speed |
| 210 m ≤ | 120 km/h |
| 160 m - 210 m | 100 km/h |
| 110 m - 160 m | 80 km/h |
| 75 m - 110 m | 60 km/h |
| 55 m - 75 m | 50 km/h |
| 40 m - 55 m | 40 km/h |
| 30 m - 40 m | 30 km/h |
| < 30 m | 20 km/h |
Combined Superelevation/Slope Gradient :
| Combined Gradient | Adaptation Speed |
| Below 10% | 120 km/h |
| 10% but below 10.5% | 80 km/h |
| Above 10.5% but below 11.5% | 50 km/h |
Road Slope :
| Slope | Adaptation Speed |
| 5% and below | 120 km/h |
| Above 5% but less than 6% | 100 km/h |
| Above 6% but less than 7% | 80 km/h |
| Above 7% but less than 8% | 60 km/h |
| Above 8% but less than 9% | 50 km/h |
| Above 9% but less than 10% | 40 km/h |
lane width (3.5 m ≤ : 120 km/h, < 3.5 m : 80 km/h)
shoulder width (1.75 m ≤ : 120 km/h, < 1.75 m : 80 km/h)