100 km/h speed limit sign
What the 100 km/h speed limit sign means: You must not drive faster than 100 km/h from this sign until the limit changes.
- Group
- Speed limit signs
- Does this group carry the law
- Enforceable. The number is a maximum for good conditions.
- In the sign deck
- 3 questions ask about this sign
What to do when you see it
- Keep to 100 km/h or less, and reduce speed for wet roads, gravel edges or heavy vehicles.
- Hold a following gap of at least two seconds, which at this speed is around 55 m.
- Plan overtaking around marked overtaking lanes rather than around gaps in oncoming traffic.
Where you see it
On rural highways, on urban motorways, and on divided roads outside built up areas.
Across the states and territories
One hundred is the common open road limit in most jurisdictions, although the default limit outside a built up area with no sign is set by each state and territory and is not always the same number. Several jurisdictions also cap learner or provisional drivers below the posted limit, so the number on the sign is not always the number you are allowed to drive. Check your own agency's rules before assuming the sign applies to you.
Tell it apart from these
- 100 km/h speed limitthis page110 km/h speed limit
The higher number appears on the better roads, usually divided highways and motorways, so the change is a signal about the road as much as about speed.
110 km/h speed limit: You must not drive faster than 110 km/h, the highest limit posted on most Australian highways.
- 100 km/h speed limitthis pageFreeway begins
The freeway sign changes the rules about who may use the road. The speed sign changes only the number.
Freeway begins: Freeway rules start here, so no pedestrians, bicycles or learner restrictions that bar the freeway, and no stopping except in an emergency.
How the knowledge tests use it
Questions here usually test the learner or provisional cap rather than the posted number, because that cap is what a learner gets wrong.
What does this sign mean?
This is a legal maximum for good conditions on that road. It applies from the sign until another speed limit sign appears.
Australian Road Rules rule 20, obeying the speed limit
Common questions
- What does the 100 km/h speed limit sign mean?
- You must not drive faster than 100 km/h from this sign until the limit changes.
- What should you do when you see a 100 km/h speed limit sign?
- Keep to 100 km/h or less, and reduce speed for wet roads, gravel edges or heavy vehicles. Hold a following gap of at least two seconds, which at this speed is around 55 m. Plan overtaking around marked overtaking lanes rather than around gaps in oncoming traffic.
- Where is the 100 km/h speed limit sign used?
- On rural highways, on urban motorways, and on divided roads outside built up areas.
- What is the 100 km/h speed limit sign confused with?
- 110 km/h speed limit: The higher number appears on the better roads, usually divided highways and motorways, so the change is a signal about the road as much as about speed. Freeway begins: The freeway sign changes the rules about who may use the road. The speed sign changes only the number.
- How do the knowledge tests ask about the 100 km/h speed limit sign?
- Questions here usually test the learner or provisional cap rather than the posted number, because that cap is what a learner gets wrong.
Try it in a question
Original practice questions, not the official bank. How we write and check them.
More speed limit signs
A number in a red circle on a white plate.