# How to Use FlightSide to Check Which Side Gets the Sun

Find out which side of the plane gets the sun on your flight. It takes about a minute, and all you need is your booking.

## Pick your airports {#airports}

Start typing where you're flying from into From, and where you're landing into To. Pick your airport from the list.

You don't need to know the airport code. Try whatever comes to mind:

- An airport code, like `LHR`
- A city, like `London`
- A code for a city with several airports, like `NYC`, `TYO` or `SEL`
- An older name, like `Bombay` or `Saigon`
- The airport's own name, like `Charles de Gaulle`

Accents are optional, so `Sao Paulo` finds São Paulo.

If you know the country but not the airport, type the country. `Italy` lists the airports in Italy, biggest first.

![The To field with "Italy" typed in, listing Rome Fiumicino, Milan Malpensa, Naples and Venice airports](/images/guide/using-flightside/airports.jpg)

## Enter your departure time {#departure}

Enter the date and time exactly as they appear on your booking. That's the local time at the airport you're leaving from, not your home time and not the arrival time. FlightSide handles the time zones and shows when you land in local time.

If you take off late at night and land the next day, use the date you take off.

![The departure date picker open on March 2027, with the 20th selected and a 12:00 PM departure time](/images/guide/using-flightside/departure.jpg)

> **Why the time matters most**
>
> Being off by an hour or two can move sunset to a different part of the flight, and that can flip which side ends up in the shade.

## Adjust the flight time (optional) {#duration}

Once both airports are in, FlightSide fills in an estimated flight time. It's usually close, so you can leave it as it is.

If you know how long your flight really takes, from a past trip or a flight tracker, type it in. If the Duration label turns amber, what you entered is far from the estimate. It's usually a typo, so give it a second look.

![The Duration field showing 1h 40m entered, with the estimate of 1h 30m beside the label](/images/guide/using-flightside/duration.jpg)

> **Why not the time on your booking?**
>
> Airlines pad their schedules, which is how a flight that leaves late can still land early. So the booked time often runs longer than the real flight. FlightSide's estimate aims at the real flight: it uses the distance, a typical cruising speed, the usual winds, and a little time for taxiing.

## See your result {#result}

That's it. The recommendation card shows which side to pick and why, and the map shows your route. [How to pick your side](/guide/how-to/pick-your-side) walks you through the card.

## Watch the sun along your flight {#timeline}

If you want to know when the sun sets, or which part of the flight is sunny on your side, use the timeline above the inputs. Drag it, and the plane moves along the route on the map with the sun moving alongside it. The labels show the local time at both ends and how long you've been flying.

![A Tokyo to Sydney flight with the timeline dragged to 4h 44m elapsed, the plane over Papua New Guinea and the sun beside it](/images/guide/using-flightside/timeline.jpg)

> **Reading the timeline**
>
> The shading shows day, twilight and night along your flight, so you can spot sunrise and sunset at a glance.

## If your flight is delayed {#delay}

If the board at the gate says delayed, you don't need to retype anything. Drag the Delay slider next to the Clear button to push your departure back, 15 minutes at a time, up to 24 hours. The result updates as you drag, so you can see right away whether the recommendation changes.

If your flight is on time, leave the slider at zero. FlightSide already allows a few minutes between leaving the gate and takeoff.

![The Delay slider set to 1h 45m, next to the Clear button](/images/guide/using-flightside/delay.jpg)

> **Tip**
>
> If your result is close to 50/50, try the slider at 15 or 30 minutes even if your flight is on time. You'll see whether a small delay would change your side before you pick a seat.

## Save or start over {#start-over}

If you want to come back to this flight later, bookmark the page. Every result has its own address, so it reopens with the same route, date and time. The same link works for sharing too: see [How to share your flight](/guide/how-to/share-your-flight).

To check another flight, press Clear and start again.

- [Pick your side](/guide/how-to/pick-your-side) — Read your result and choose the right window seat.
- [Use offline](/guide/how-to/use-offline) — Install FlightSide and check your seat with no signal.
- [FAQ](/guide/faq) — Quick answers about the sun, seats and routes.