TSA’s app can help you plan ahead for your trip.

Surprises can be wonderful. But beyond the surprises first class upgradeMost of us want to know what to do when traveling.

This is especially true when it comes to wait times at airport security — especially after a summer that saw the 10 busiest days ever recorded at Transportation Security Administration checkpoints.

Some of my most stressful airport experiences have been arriving late to the airport for one reason or another and then having to queue for security and wait for minutes to pass.

Sure, this is where programs like Clear and TSA PreCheck can be a lifesaver. They offer significant time savings, even if your PreCheck membership is already burst to record the number.

But TSA also offers another way to plan ahead and predict security check wait times — right on your smartphone.

Read more: Ways to Get TSA PreCheck, Global Entry, and Clear for Free or at a Discount

MyTSA App

TSA has a free mobile app you can download: MyTSA App.

It shows current security wait times at checkpoints nationwide. Plus, it predicts future wait times at the terminal you’re going to — down to the date and time.

How to use the TSA app

Once you log in, you’ll see a screen like the one below. This screen shows the closest airport to you and the current wait times. At the time of writing, I’m near Chicago’s O’Hare International Airport (ORD), where wait times range from 15 to 30 minutes.

You can also add an airport—such as the one closest to your home—to your list as a “favorite airport.” In my case, that’s Raleigh-Durham International Airport (RDU) in North Carolina. The wait time when I searched was under 15 minutes.

Additionally, you can search for any airport across the country.

I searched New York City’s LaGuardia Airport (LGA) and found estimated wait times of 15 to 30 minutes.

You can also narrow information down to specific terminals, like Terminal C, where Delta Air Lines operates its LaGuardia hub.

The app also shows whether the Federal Aviation Administration’s delay program is in place; this may not have much of an impact on security wait times, but it could mean widespread flight delays.

Estimated future wait times

The app can also help you plan for future estimated wait times based on past data.

Let’s say you’re planning on flying out of LaGuardia on Friday morning, which is usually busiest day of the week. You can use the app to see what LaGuardia’s TSA checkpoints typically look like from 6 a.m. to 7 a.m. on Fridays.

This means that wait times typically last 15 to 30 minutes during that time, and wait times can be longer in the afternoon.

Remember that if you have TSA PreCheckYour wait time will definitely be shorter. As the app points out, most TSA PreCheck passengers (nationwide) have to wait five minutes or less.

Check for 3-1-1 compliance

You can also use the app to double-check that the items in your carry-on bag comply with agency regulations. rules for liquids and prohibited items.

After my electric razor recently broke, I felt compelled to double check if disposable razors were allowed in carry-on luggage. I typed it into the search bar on the app and saw that I was allowed to bring one.

On the other hand, if you search for “peanut butter,” you’ll find that this product is prohibited in quantities larger than 3.4 ounces.

The last line

Planning ahead is key when flying. The MyTSA app can help you see what security screenings are likely to take place — along with many other helpful features.

That — plus enrolling in time-saving programs like Clear and Global Entry or TSA PreCheck (and taking advantage of the filing fee rebate offered by some travel credit cards) — can help make security checks more predictable.

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