Speed limits and stopping distances theory test practice
Free, no accountBased on the Rules of the Road
What you need to know
Irish speed limits are in kilometres per hour and are shown on round signs with a red border. If there is no sign, a default limit applies depending on the type of road: 120 km/h on motorways, 100 km/h on national roads, 80 km/h on regional roads and 50 km/h in built-up areas. Rural local roads now default to 60 km/h. Local authorities can set different limits, such as 30 or 40 km/h, with signs.
A speed limit is a maximum, not a target. You must drive at a speed that suits the road, the traffic and the weather, and that lets you stop within the distance you can see to be clear. Some vehicles have lower limits: a car towing a trailer or caravan is limited to 80 km/h on all roads. Always obey the lower of the vehicle limit and the road limit.
Stopping distance is thinking distance plus braking distance. Thinking distance is how far you travel before you react, and braking distance is how far you travel once the brakes are on. On a dry road at 100 km/h the total is about 70 metres. Braking distance grows much faster than speed: double your speed and you need nearly four times the braking distance.
Keep a gap behind the vehicle in front. Use the two-second rule on a dry road: pick a fixed object, let the car ahead pass it, and count two seconds before you reach it. Double the gap in the wet, and allow four to five seconds in snow, fog or ice. If you hit the car in front, the driver behind is usually held responsible.
Rules of the Road: Speed limits · Following and stopping distances
20 practice questions
Pick an answer to see whether it is right and why.
What is the default speed limit on a motorway in Ireland?
Mark one answer · keys A to D
All the questions with answers
1. What is the default speed limit on a motorway in Ireland?
Answer: 120 km/h
The default limit on a motorway is 120 km/h unless signs show a lower one.
Rules of the Road: Speed limits
2. What is the default speed limit on a national road, such as an N road, unless signs say otherwise?
Answer: 100 km/h
National roads have a default limit of 100 km/h.
Rules of the Road: Speed limits
3. What is the default speed limit in a built-up area when there is no other sign?
Answer: 50 km/h
The default limit in built-up areas is 50 km/h, and many areas have lower limits signed.
Rules of the Road: Speed limits
4. What does a round sign with a red border and the number 60 mean?
Answer: The maximum speed is 60 km/h
Red-bordered round signs show a maximum speed in kilometres per hour.
Rules of the Road: Speed limits
5. You are towing a caravan on a national road. What is the highest speed you may drive at?
Answer: 80 km/h
A vehicle towing a trailer or caravan is limited to 80 km/h on all roads.
Rules of the Road: Speed limits
6. You are driving on a regional road with no speed limit signs. What is the default limit?
Answer: 80 km/h
Regional roads have a default limit of 80 km/h.
Rules of the Road: Speed limits
7. What is the main purpose of the two-second rule?
Answer: To keep a safe gap behind the vehicle in front
The two-second rule helps you keep enough space to react and stop if the vehicle ahead brakes.
Rules of the Road: Following and stopping distances
8. You are driving in heavy rain. How should you change your following gap?
Answer: Double the gap you would leave in the dry
In wet conditions, you should double the two-second gap because stopping takes longer.
Rules of the Road: Following and stopping distances
9. In fog, snow or ice, how much time gap should you aim for behind the vehicle in front?
Answer: Four to five seconds
In snow, fog or ice, allow four to five seconds because stopping distances are much longer.
Rules of the Road: Following and stopping distances
10. Stopping distance is made up of which two parts?
Answer: Thinking distance and braking distance
Thinking distance is covered before you react, and braking distance after the brakes are applied.
Rules of the Road: Following and stopping distances
11. You double your speed. What happens to your braking distance?
Answer: It becomes about four times longer
Braking distance increases much faster than speed. Doubling speed means roughly four times the braking distance.
Rules of the Road: Following and stopping distances
12. Roughly what is the total stopping distance on a dry road at 50 km/h?
Answer: 25 metres
On a dry road at 50 km/h, thinking distance is about 10 m and braking distance about 15 m, so about 25 m in total.
Rules of the Road: Following and stopping distances
13. Roughly what is the total stopping distance on a dry road at 100 km/h?
Answer: 70 metres
At 100 km/h on a dry road you need about 20 m thinking distance plus 50 m braking distance, so about 70 m.
Rules of the Road: Following and stopping distances
14. What can make your thinking distance longer?
Answer: Being tired or distracted
Tiredness, distraction and alcohol all slow your reaction, so you travel further before you start braking.
Rules of the Road: Following and stopping distances
15. You are overtaking a lorry on a road with an 80 km/h limit. May you exceed 80 km/h to get past?
Answer: No, the limit applies when overtaking
You must not exceed the speed limit even when you are overtaking.
Rules of the Road: Speed limits
16. What does the speed limit on a sign tell you?
Answer: The most you may drive, in good conditions
A limit is a maximum, not a target. In poor conditions the safe speed may be much lower.
Rules of the Road: Speed limits
17. Which of these is the best way to drive on an icy road?
Answer: Slowly, with extra distance and gentle controls
Ice greatly lengthens stopping distances, so drive slowly, leave a big gap and brake and steer gently.
Rules of the Road: Following and stopping distances
18. The road is wet and your speed is within the limit. What is the best approach?
Answer: Drive at a speed that suits the conditions
You must drive to the conditions, which in wet weather often means below the limit.
Rules of the Road: Speed limits
19. Why should you avoid using cruise control in heavy rain, snow, fog or on ice?
Answer: You may not react in time to a loss of grip
Cruise control can make it harder to react to changing grip, so avoid it in poor conditions.
Rules of the Road: Following and stopping distances
20. You are on a rural local road with no speed limit signs. What is the default limit?
Answer: 60 km/h
Rural local roads have had a default limit of 60 km/h since February 2025, while regional roads stay at 80 km/h.
Rules of the Road: Speed limits
Questions people ask
- What is the speed limit on a national road in Ireland?
- The default limit on a national road is 100 km/h, unless a sign shows a different limit. National roads have green signs with an N number.
- What is the speed limit on a motorway in Ireland?
- The default motorway limit is 120 km/h. Learner permit holders cannot drive on motorways at all, and some motorway sections have lower limits shown on signs.
- What is the two-second rule?
- It is a way of checking you have a safe gap to the vehicle in front. When it passes a fixed object, you should not reach the same object in less than two seconds. Double the gap on wet roads.
- What is the speed limit in a built-up area in Ireland?
- The default limit in a built-up area is 50 km/h unless signs show a lower limit, such as 30 km/h. Many towns are reducing their limits, so always read the signs.
Other theory test topics
- Learner permits and licences
- Penalty points and offences
- Alcohol, drugs, phones and fatigue
- Vehicle safety and passengers
- Junctions and right of way
- Roundabouts and turning
- Road signs and markings
- Motorways, overtaking and lanes
- Pedestrians, cyclists and other road users
- Parking and stopping
- Hazards, emergencies and breakdowns
Rules summarised from the Rules of the Road (© Road Safety Authority). Questions written by PassRank. These are not the official Driver Theory Test questions.