What is the minimum age for a CDL?

Federal rules set 21 to drive a commercial vehicle across state lines. Most states allow 18 for driving only inside the state; the table shows each one.

How long do you have to hold a CLP before the CDL skills test?

At least 14 days under federal rules. Some states set a longer wait, like DC (30 calendar days) and Pennsylvania (15 days).

What score do you need to pass the CDL knowledge test?

At least 80 percent on each knowledge test, under federal rules. States can show their own count of questions; the state pages list the ones that publish it.

You are hauling cargo. When must you first check how it is tied down after you start the trip?

Before you leave the yard, and not again

After that first check, how often must you check how the cargo is tied down?

Every 150 miles or every 3 hours, whichever comes first

A tire on your truck was just changed. What should you do?

Stop a short while later and check that the wheel nuts are still tight

Drive at least 100 miles before you check anything

Let some air out of the new tire

Nothing, because the shop already checked it

If you double your speed from 20 mph to 40 mph, what happens to your braking distance?

It becomes about 4 times longer

It becomes about 8 times longer

How much should you slow down on a wet road?

Keep the same speed and brake earlier

Slow down by about three-quarters

How much should you slow down on packed snow?

Not at all if you have chains on

Your truck starts to hydroplane on standing water. What should you do?

Take your foot off the accelerator and push in the clutch

Steer sharply toward the shoulder

Speed up to push through the water

What is the safe way to take a curve?

Slow to a safe speed before you enter the curve

Brake in the middle of the curve

Shift to neutral and coast through

Speed up before the curve so you can coast

You are about to go down a long, steep grade. When should you shift to a low gear?

Before you start down the grade

Once your speed starts to build

Your safe speed on a downgrade is 40 mph. You are in the right low gear and reach 40 mph. What should you do?

Brake firmly until you slow to about 35 mph, then let off the brakes

Brake until you stop, then start again

Keep light pressure on the brakes all the way down

Wait until you reach 50 mph, then brake

What can happen if some of your brakes are out of adjustment?

The other brakes do more work, overheat and can fade

Nothing, as long as most brakes work

Why does an empty truck need more distance to stop than a loaded one?

An empty truck has less traction

It does not; empty trucks stop in a shorter distance

Only the tires matter, not the load

You stop on a divided highway. Where do the three warning triangles go?

10, 100 and 200 feet toward the approaching traffic

10, 50 and 100 feet behind the truck

100 feet ahead and 100 feet behind

You stop on a two-lane road with traffic in both directions. Where do the triangles go?

One within 10 feet of a front or rear corner, one 100 feet behind and one 100 feet ahead

All three behind the truck, 50 feet apart

Two in front and one at a corner

You must stop at a railroad crossing that has no white stop line. Where do you stop?

No closer than 15 feet and no more than 50 feet from the nearest rail

No closer than 5 feet from the rail

Your truck gets stuck on the railroad tracks. What should you do?

Get out, move away from the tracks, and call the number posted at the crossing or 911

Stay in the cab and sound the horn

Rock the truck back and forth to get free

Unhook the trailer and drive off

What is "controlled braking"?

Braking as hard as you can without locking the wheels

Pumping the brake pedal as fast as you can

Pushing the pedal to the floor and holding it

You must steer quickly to miss a crash. What should you avoid?

Holding the wheel with both hands

Turning only as much as you need to

A front tire blows out. What should you do first?

Hold the steering wheel firmly and stay off the brake until the truck slows down

Steer onto the shoulder at once

The yellow ABS malfunction lamp stays on while you drive. What does it mean?

You may have lost antilock braking, but you still have regular brakes. Drive normally and get it fixed soon.

All of your brakes have failed. Stop in the lane.

You should turn the engine off and on while driving.

Nothing. The lamp always stays on.

The rear drive wheels lock up and start to skid. What should you do?

Stop braking, then counter-steer

What causes most front-wheel skids?

Driving too fast for conditions

You are at an accident scene. What is the first thing to do?

Protect the area so another crash does not happen there

Your engine catches fire. What should you do?

Turn off the engine and avoid opening the hood if you can

Open the hood wide to see the fire

Keep driving to the nearest service station

There is a fire in the cargo of your closed van trailer. What should you do with the doors?

Spray water in through the doors

Where do you aim a fire extinguisher?

At the base or source of the fire

Which use of a phone is allowed while you drive a commercial vehicle?

Talking on a hands-free phone that is close to you

Holding the phone to your ear to talk

Dialing by pressing several buttons

Reaching across the cab for your phone

How many tie-downs does cargo need?

At least one for every 10 feet of cargo, and never fewer than two

How should you load heavy cargo?

As low as possible, with the heaviest parts under the lightest

CDL Requirements by State 2026: All 50 States and DC

CDL requirements in every state

Each row comes from that state's DMV pages or CDL manual. A dash means no official page we checked settled the fee; the state page says why.

State	Age in state / across states	Hold the permit	Passing score	Permit fee
Alabama	18 / 21 (federal)	14 days	80% (federal)	$36.25
Alaska	18 / 21	14 days	80%	$15
Arizona	18 / 21	14 days	80%	$25
Arkansas	18 / 21	14 days	80% (federal)	-
California	18 / 21	14 days	80% (federal)	-
Colorado	18 / 21	14 calendar days	80% (federal)	$20
Connecticut	18 / 21	14 days	80%	$20
Delaware	18 / 21	14 full days	80% (federal)	$5
District of Columbia	18 (Class C only) / 21	30 calendar days	80% (federal)	$78
Florida	18 / 21	14 days	80% (federal)	-
Georgia	18 / 21	14 days	80% (federal)	$10
Hawaii	- / 21	14 days	80% (federal)	$30
Idaho	18 / 21	14 days	80% (federal)	$29
Illinois	18 / 21	14 days	80%	$50
Indiana	18 / 21	14 days	80% (federal)	$17
Iowa	18 / 21	14 days	80%	$12
Kansas	18 / 21	14 days	80% (federal)	$13
Kentucky	18 / 21	14 days	80% (federal)	$11
Louisiana	18 / 21	14 days	80% (federal)	-
Maine	18 / 21 (federal)	14 days	80% (federal)	-
Maryland	18 / 21	14 days	80% (federal)	$106
Massachusetts	18 / 21	14 days	80%	$30
Michigan	18 / 21	14 days	80%	-
Minnesota	18 / 21	14 calendar days	80% (federal)	$26.75
Mississippi	18 / 21 (federal)	14 days	80% (federal)	$16
Missouri	18 / 21	14 days	80% (federal)	$44
Montana	18 / 21	14 days	80% (federal)	$41.72
Nebraska	18 / 21	14 days	80% (federal)	$15
Nevada	18 / 21	14 days	80% (federal)	$57.50
New Hampshire	18 / 21	14 days	80%	$20
New Jersey	18 / 21	14 days	80%	$125
New Mexico	18 / 21	14 days	80%	$10
New York	18 / 21	14 days	80%	$10
North Carolina	18 / 21	14 days	80% (federal)	$25.50
North Dakota	18 / 21	14 days	80% (federal)	$15
Ohio	18 / 21	14 days	80% (federal)	$31.50
Oklahoma	18 / 21 (federal)	14 full days	80% (federal)	-
Oregon	18 / 21	14 days	80% (federal)	$40
Pennsylvania	18 / 21	15 days	80% (federal)	-
Rhode Island	18 / 21	14 days	80% (federal)	$73.50
South Carolina	18 / 21	14 days	80% (federal)	$2.50
South Dakota	18 / 21	14 days	80% (federal)	$43
Tennessee	18 / 21	14 days	80% (federal)	$14
Texas	18 / 21	14 days	80%	$25
Utah	18 / 21	14 days	80%	-
Vermont	18 / 21	14 days	80% (federal)	$18
Virginia	18 / 21	14 days	80%	$3
Washington	18 / 21	14 days	80%	$40
West Virginia	18 / 21	14 days	80%	-
Wisconsin	18 / 21	14 days	80%	$30
Wyoming	18 / 21	14 days	80%	$45

From each state's DMV pages and CDL manual, checked 2026-10-20. "(federal)" means the state does not publish its own age or passing score, so the federal rule is shown.

CDL general knowledge practice test

Question 1 of 10 · Vehicle inspection

How much tread depth do the front tires need, at a minimum, in every major groove?

What every state requires

Age: 21 to drive a commercial vehicle across state lines. Most states let you drive only inside the state at 18.
Permit: pass the knowledge tests to get a commercial learner's permit (CLP), then hold it at least 14 days before the skills test. Some states make you wait longer.
Passing score: at least 80 percent on each knowledge test (49 CFR 383.135).
Training: since February 7, 2022, a first Class A or Class B CDL, a move up from Class B to Class A, and a first school bus or passenger endorsement need entry-level driver training from a provider on the FMCSA Training Provider Registry before the skills test. For a first hazmat endorsement, the training comes before the hazmat knowledge test.
Skills test: the vehicle inspection, basic vehicle control and the road test.

After the CDL: the job

Look at the CDL driver openings near you and get your resume written for each one. To get ready, take the free practice test on this page and walk through the pre-trip inspection checklist.

All 40 questions with answers

How much tread depth do the front tires need, at a minimum, in every major groove?
Answer: 4/32 inch. Front tires need at least 4/32 inch of tread in every major groove. The other tires need at least 2/32 inch.
You are hauling cargo. When must you first check how it is tied down after you start the trip?
Answer: Within the first 50 miles. Check the cargo and its tie-downs within the first 50 miles of the trip, then keep checking it as you go.
After that first check, how often must you check how the cargo is tied down?
Answer: Every 150 miles or every 3 hours, whichever comes first. After the first 50 miles, check again every 150 miles or every 3 hours, whichever comes first, and after every break.
A tire on your truck was just changed. What should you do?
Answer: Stop a short while later and check that the wheel nuts are still tight. Wheel nuts can loosen after a tire change. Stop a short while later and recheck that they are tight.
How far ahead do most good drivers look?
Answer: 12 to 15 seconds ahead. Look 12 to 15 seconds ahead, so you have time to slow down or change lanes before you reach a problem.
At highway speed, about how far is 12 to 15 seconds ahead?
Answer: About a quarter of a mile. At highway speeds, 12 to 15 seconds is about a quarter of a mile. In town it is about one block.
You drive a 40-foot truck at under 40 mph. How much following distance should you keep?
Answer: 4 seconds. Keep 1 second for every 10 feet of vehicle length below 40 mph. A 40-foot truck needs 4 seconds.
You drive a 50-foot truck at over 40 mph. How much following distance should you keep?
Answer: 6 seconds. One second per 10 feet gives 5 seconds. Above 40 mph, add 1 more second, for 6 seconds.
In ideal conditions at 55 mph, about how far will your truck travel before it stops, counting the time to see, react and brake?
Answer: About 419 feet. The manual adds about 142 feet to recognize the hazard, 61 feet to react and 216 feet to brake, for at least 419 feet.
If you double your speed from 20 mph to 40 mph, what happens to your braking distance?
Answer: It becomes about 4 times longer. Doubling your speed makes the braking distance and the force of a crash about 4 times greater.
How much should you slow down on a wet road?
Answer: Slow down by about one-third. Wet roads can double your stopping distance. Slow down by about one-third, for example from 55 to about 35 mph.
How much should you slow down on packed snow?
Answer: By half or more. On packed snow, cut your speed by half or more. On ice, slow to a crawl and stop as soon as it is safe.
When the temperature drops near freezing, which part of the road usually freezes first?
Answer: Bridges. Bridges freeze before the rest of the road. Be extra careful on them when it is close to 32 degrees.
Your truck starts to hydroplane on standing water. What should you do?
Answer: Take your foot off the accelerator and push in the clutch. Release the accelerator and push in the clutch so the wheels turn freely. Do not use the brakes to slow down.
What is the safe way to take a curve?
Answer: Slow to a safe speed before you enter the curve. Slow down before the curve. Braking in a curve can lock the wheels and cause a skid, and a tall truck can roll over even at the posted curve speed.
You are about to go down a long, steep grade. When should you shift to a low gear?
Answer: Before you start down the grade. Shift down before the grade. Once speed builds up you may not be able to get into a lower gear, and you can lose all engine braking.
Your safe speed on a downgrade is 40 mph. You are in the right low gear and reach 40 mph. What should you do?
Answer: Brake firmly until you slow to about 35 mph, then let off the brakes. Brake hard enough to feel a clear slowdown to about 5 mph under your safe speed, then release. Repeat each time you reach the safe speed.
What can happen if some of your brakes are out of adjustment?
Answer: The other brakes do more work, overheat and can fade. Brakes out of adjustment stop doing their share. The others overheat and fade, so check adjustment often.
Why does an empty truck need more distance to stop than a loaded one?
Answer: An empty truck has less traction. Brakes, tires and springs work best when the truck is loaded. An empty truck has less traction, so it needs more room to stop.
You must stop on the shoulder of a road. How soon must your warning triangles be out?
Answer: Within 10 minutes. Turn on your four-way flashers and put out your warning devices within 10 minutes of stopping.
You stop on a divided highway. Where do the three warning triangles go?
Answer: 10, 100 and 200 feet toward the approaching traffic. On a one-way or divided highway, place them 10 feet, 100 feet and 200 feet toward the traffic coming at you.
You stop on a two-lane road with traffic in both directions. Where do the triangles go?
Answer: One within 10 feet of a front or rear corner, one 100 feet behind and one 100 feet ahead. On a two-way road, mark the truck within 10 feet of a front or rear corner, then put one 100 feet behind and one 100 feet ahead.
You must stop at a railroad crossing that has no white stop line. Where do you stop?
Answer: No closer than 15 feet and no more than 50 feet from the nearest rail. With no stop line, stop no closer than 15 feet and no farther than 50 feet from the nearest rail.
About how long does a typical tractor-trailer take to clear a single railroad track?
Answer: At least 14 seconds. A typical tractor-trailer needs at least 14 seconds to clear one track and more than 15 seconds for two. Be sure you can get all the way across before you start.
Your truck gets stuck on the railroad tracks. What should you do?
Answer: Get out, move away from the tracks, and call the number posted at the crossing or 911. Get out and away from the tracks. Call the emergency number on the crossing sign or 911, and give the crossing's DOT number if it is posted.
What is "controlled braking"?
Answer: Braking as hard as you can without locking the wheels. In controlled braking you brake as hard as you can without locking the wheels, and keep steering movements very small.
You must steer quickly to miss a crash. What should you avoid?
Answer: Braking while you are turning. Do not brake while you turn. It is easy to lock the wheels and skid out of control.
A front tire blows out. What should you do first?
Answer: Hold the steering wheel firmly and stay off the brake until the truck slows down. Hold the wheel firmly with both hands. Stay off the brake until the truck slows, then brake gently and pull off the road.
The yellow ABS malfunction lamp stays on while you drive. What does it mean?
Answer: You may have lost antilock braking, but you still have regular brakes. Drive normally and get it fixed soon. A lamp that stays on means ABS may not be working on one or more wheels. Your regular brakes still work, so drive normally and have it serviced soon.
The rear drive wheels lock up and start to skid. What should you do?
Answer: Stop braking, then counter-steer. Let off the brakes so the rear wheels roll again, then counter-steer as the truck comes back on course.
What causes most front-wheel skids?
Answer: Driving too fast for conditions. Most front-wheel skids come from driving too fast for conditions. Worn front tires and too little weight on the front axle also cause them.
You are at an accident scene. What is the first thing to do?
Answer: Protect the area so another crash does not happen there. First keep another crash from happening: move your truck off the road if you can, turn on your flashers and put out triangles.
Your engine catches fire. What should you do?
Answer: Turn off the engine and avoid opening the hood if you can. Turn off the engine and do not open the hood if you can avoid it. Spray through the vents (louvers), the radiator or from underneath, and never pull into a service station.
There is a fire in the cargo of your closed van trailer. What should you do with the doors?
Answer: Keep them shut. Keep the doors shut. Opening them feeds the fire air and can make it burn very fast, especially with hazardous cargo.
Where do you aim a fire extinguisher?
Answer: At the base or source of the fire. Aim at the base of the fire, stay as far back as you can, and stand upwind so the wind carries the spray to the fire.
It is illegal to drive a commercial vehicle with a blood alcohol concentration of:
Answer: .04% or more. At .04% or more it is illegal, and a first offense costs your CDL for at least one year. Any detectable alcohol under .04% still puts you out of service for 24 hours.
What sobers a person up after drinking?
Answer: Only time. The liver clears alcohol at a fixed rate, about one-third of an ounce an hour. Only time works.
Which use of a phone is allowed while you drive a commercial vehicle?
Answer: Talking on a hands-free phone that is close to you. You may only use a hands-free phone that is close to you. Holding it, dialing with more than one button or reaching for it is not allowed, except to call for help in an emergency.
How many tie-downs does cargo need?
Answer: At least one for every 10 feet of cargo, and never fewer than two. Use at least one tie-down for every 10 feet of cargo. Even small cargo needs at least two.
How should you load heavy cargo?
Answer: As low as possible, with the heaviest parts under the lightest. A high center of gravity makes rollover more likely. Keep cargo low and put the heaviest parts under the lightest.

CDL Requirements by State (2026): Age, Permit Wait, Passing Score and Fees for All 50 States and DC