How to Track and Predict Cheap Flights for Any Route (Spreadsheet Template + Weekly Workflow)

Overview

A flight price tracker cannot guarantee the lowest fare. It can, however, show whether today’s price is low, typical, or unusually high compared with the prices you have observed for the same route and travel conditions.

The key is consistency. A $180 fare for a nonstop flight with a carry-on included is not directly comparable with a $150 basic economy fare that requires a checked bag or has a different airport. Record enough detail to compare like with like, then use the results as a decision aid rather than a promise about future prices.

You can build the tracker in Google Sheets, Excel, or another spreadsheet application. Create one row for every price observation. A useful starting template is:

Date checked,Origin,Destination,Departure date,Return date,Trip type,Airline,Stops,Departure time,Base fare,Taxes and fees,Bags or seats,Total comparable fare,Currency,Days before departure,Search weekday,Source,Notes

Save a copy of the sheet with a clear route name, such as JFK-LAX-roundtrip. If your preferred booking site allows a CSV export, import it into the raw-data tab. If not, enter the displayed total manually or record a nightly screenshot and transcribe the relevant details during your weekly review.

For broader price-alert coverage, pair the spreadsheet with the alert process described in How to Set Up Flight Price Alerts and Track Airfare Drops. The alert can tell you that a change occurred; the spreadsheet helps you judge whether the new fare fits your route history.

How to estimate

Start with a defined search rather than collecting random fares. Choose the origin airport, destination airport, travel dates or date range, cabin, passenger count, and acceptable connection pattern. If you are comparing nearby airports, keep those results in a separate route group so the median is not distorted by a different itinerary.

1. Normalize the fare

Use one comparable total in the tracker. A practical formula is:

Comparable fare = ticket total + required fees for your trip - optional extras you would not purchase

For example, add a bag only when you would actually travel with one. Record optional seat selection separately unless the seat is essential to your plans. Keep the original displayed fare in its own column so you can audit your calculation later. If prices are in different currencies, either track each currency separately or convert them using the same conversion method and date for every observation.

2. Calculate days before departure

If the departure date is in column D and the check date is in column A, a spreadsheet formula can be:

=D2-A2

Format the result as a number. Group observations into practical windows such as 0–7, 8–14, 15–30, 31–60, and 61–90 days before departure. These are tracking categories, not universal rules about the best time to book flights.

3. Use the median, not only the lowest fare

The lowest price may be a brief sale, a different itinerary, or a data-entry error. A median gives you a better view of the middle of your observations. In a spreadsheet, a basic formula is:

=MEDIAN(M2:M20)

Replace the range with the comparable-fare column for the group you are evaluating. A pivot table can summarize median fare by days-before-departure window, airline, number of stops, or search weekday. If your spreadsheet does not offer a median aggregation in a pivot table, calculate the median from a filtered range in a separate summary table.

4. Create a simple buy signal

Set a target price before you become attached to a particular fare. You can base it on your budget, the route’s tracked median, or both. One simple signal compares the current fare with the median for its current booking window:

=IF(CurrentFare<=TargetPrice,"BUY REVIEW",IF(CurrentFare<=WindowMedian,"CONSIDER","WAIT AND TRACK"))

“BUY REVIEW” means the fare deserves an immediate check of baggage rules, cancellation terms, airport, schedule, and payment total. It does not mean you must buy. “CONSIDER” means the fare is within the range you have observed. “WAIT AND TRACK” means the fare is above your chosen threshold, provided your dates remain flexible and the risk of waiting is acceptable.

Inputs and assumptions

A useful tracker depends more on clean inputs than on complicated formulas. Add these fields when they affect your decision:

• Route: Record exact airports, not only city names. Nearby airports can produce different schedules and total costs.
• Dates and flexibility: Mark fixed dates separately from searches allowing one or more days of flexibility.
• Itinerary type: Separate nonstop, one-stop, and self-transfer results. A lower fare may carry more time or connection risk.
• Fare conditions: Record basic economy, main cabin, or another fare category. Compare the true cost using the guidance in How to Compare the True Cost of a Flight.
• Included services: Note whether the displayed total includes a carry-on, checked bag, seat, or other item you need.
• Search source and timestamp: Prices can change between the initial search and checkout, so keep the time and source for context.

For a new route, collect observations for as long as your booking timeline allows. A 30-day lookback can provide a quick reference, while 60- and 90-day lookbacks may reveal more variation. Do not combine all three windows without labeling them; older observations may describe a different schedule, season, or fare mix.

When data is sparse, avoid drawing a strong conclusion from one or two prices. Widen the date range, include an additional search weekday, or create a separate comparison for a nearby airport. If the route has a new airline, changed schedule, or different baggage structure, start a new comparison group rather than treating the old data as fully equivalent.

Worked examples

Suppose you are tracking a round trip between two fixed airports for a departure 42 days away. You have recorded comparable fares for similar nonstop itineraries in the 31–60-day window. The observations are 212, 228, 235, 249, and 310 in the same currency. The median is 235, while the current fare is 218.

The spreadsheet would classify 218 as below the tracked median. Before purchasing, review the fare conditions and total checkout amount. If a carry-on or seat is necessary but not included, add that cost before comparing the result with your target price. If the adjusted fare remains below your target, the “BUY REVIEW” signal is reasonable. If the added services move it above your target, the signal should become “CONSIDER” or “WAIT AND TRACK,” depending on your flexibility.

Now consider a second route with only three observations: 180, 260, and 295. The median is 260, but that small sample may not represent the route well. Treat the result as provisional. Add more observations, compare a nearby airport, and check whether the three fares have the same stops, cabin, and baggage conditions. This is where a tracker is most valuable: it makes uncertainty visible instead of hiding it behind a single “cheapest” result.

Your weekly workflow can be brief:

1. Search the same route and date conditions.
2. Record the total fare and required extras.
3. Paste new CSV rows or enter the observation from a screenshot.
4. Refresh formulas and pivot tables.
5. Compare the current fare with the target and relevant window median.
6. Check the itinerary and fare rules before acting.

When to recalculate

Refresh the tracker at least weekly while you are actively planning, and more often when your travel date is approaching or your dates are fixed. Recalculate immediately when the airline changes the schedule, a new carrier enters the route, an airport option changes, or baggage and fare rules alter the comparable total.

Review the target price before major sale periods, after a change in your travel requirements, or when you switch from a personal item to a carry-on or checked bag. Also recalculate after changing the search from nonstop to connecting flights, or from a standard ticket to basic economy. These are different products and should not share one benchmark.

Before buying, use this final checklist:

• Is the fare for the correct airports and dates?
• Is it being compared with similar stops, times, and cabin conditions?
• Have required baggage, seat, and payment costs been included?
• Is the fare at or below your target, or is waiting worth the risk?
• Have you checked the airline’s current rules for changes, cancellations, and credits?

Keep the raw observations instead of replacing them with the latest summary. That history is what makes the spreadsheet useful when you revisit the route. For additional context on flexible dates, see Best Time to Book Flights: A Flexible-Date Planning Guide; for connection risk, see Self-Transfer and Connecting Flights: A Risk Checklist. The goal is not to predict every fare movement. It is to make a careful, repeatable decision with the information available when you need to book.