TD First Class Travel® Visa Infinite* CardTD First Class Travel® Visa Infinite* CardUp to 160,000 TD Rewards Points + annual fee rebate for the first year

How does Great Circle Mapper – GCMap work?

How does Great Circle Mapper – GCMap work?
Share

How does Great Circle Mapper – GCMap work?

Great Circle Mapper – also known as GCMap or GCM – is a tool I regularly use. It provides a wealth of information on airports and the distances between two or more destinations.

It is a particularly useful tool for flyer programs of airlines whose pricing is linked to the distance travelled. It’s the case with British Airways Executive Club or the new Air Canada Aeroplan program.

It is also an ideal tool to visually present a route on a map, which is particularly used within the milesopedia member community.

Great Circle Mapper – GCMap settings

There are several parameters to be aware of depending on your objectives.

Characters to know

Before getting to the heart of the matter, you should first know that there are four main characters to know with GCMAP:

  • A dash «  » allows to link destinations together
  • A comma « , » separates the queries
  • A crossbar « / » allows to duplicate queries with the first one
  • An arobase « @ » allows you to base a query from an airport

Calculate distances between destinations

To calculate distances between different destinations (and draw routes on a map ), you will essentially need to use the hyphen « -« , the comma « , » and the crossbar « / ».

Here are the different actions possible with GCMAP:

GoalExample
Travel between 2 airports – one wayYUL-ZRH
Travel between 2 airports – round tripYUL-ZRH-YUL
Travel between 2 airports – one way (different departure point)YUL-ZRH,YYZ-ZRH
Travel between several one-way destinationsYUL-ZRH-IST
Travel between several return destinationsYUL-ZRH-IST-YUL
Travel between several destinations – multi-cityYUL-ZRH,ZRH-IST,IST-YUL
Travel to several destinations from one airportYUL-MIA/MSY/DFW/EWR/YYZ/DEN
Travel between several destinations – multi-city from an airportYUL-ZRH-IST/BCN/CDG/TLV/CAI
How does Great Circle Mapper - GCMap work? - Gcm Multi Segments

Draw radiuses from a destination

To draw radiuses on a map , you will have to use the arobase « @ », combined with a distance.

Here are the different actions possible with GCMAP:

GoalExample
Radius from an airport1500mi@YUL
Multiple radiuses from an airport500mi@YUL,1500mi@YUL,2750mi@YUL
Travel to several destinations from one airportYUL-YYZ/EWR/MSY/MIA/DFW/DEN/SFO

Once you have entered your radius(es), anything you enter in the search field will also display the radiuses on the map. It’s quite useful as part of the new Aeroplan program to quickly view direct flights and limits.

How does Great Circle Mapper - GCMap work? - Gcm Distance Yul Map

Compare distances

To compare distances between different destinations (and to draw routes on a map), the hyphen « – » and the comma « , » should be used.

Here are the different actions possible with GCMAP:

GoalExample
Travel between 2 airports – one-way vs. connections (+10%)YUL-SIN,YUL-IST-SIN
Travel between 2 airports – one-way vs. connections (+60%)YUL-SIN,YUL-IST-JNB-SIN
Travel between 2 airports – one-way vs. connections (+122%)YUL-SIN,YUL-IST-JNB-AUH-ICN-SIN
How does Great Circle Mapper - GCMap work? - Gcm Yul Sin Yul Ist Sin
How does Great Circle Mapper - GCMap work? - Gcm Yul Sin Yul Ist Jnb Sin
How does Great Circle Mapper - GCMap work? - Gcm Yul Sin Yul Ist Jnb Auh Icn Sin

Conclusion

You can do other things with GCMAP, like changing the path colours or the map format, but the parameters shown in this article are enough to get started with the tool!

Annual fee
$150
Our valuation
$350

Milesopedia first-year estimateFirst-year valueWelcome bonus$350Total$350Rewards on your spending are not included. The calculator that adds them from your own profile is on the card's page.

Welcome offer
Up to 35,000 points

Ends Nov 1, 2026

Apply Now

on Scotiabank's website

With this welcome offer for the Scotiabank Passport Visa Infinite +* Card +* CardMC, you’ll earn 25,000 welcome bonus Scene+ points after charging $2,000 in purchases to your account within the first three months.

Plus, every year, earn an annual bonus of at least 10,000 Scene+ points when you charge at least $40,000 in purchases to your account. In total, the offer represents up to 35,000 Scene+ points and a value of up to $1,250 in the first year, including rewards, savings on foreign transaction fees and airport lounge access.

With the Scotiabank Passport Visa Infinite +* Card, you earn 3 points per $1 spent at Sobeys, IGA, Safeway, Foodland and participating Co-ops, and 2 points per $1 spent at other grocery stores, restaurants, eligible entertainment and eligible daily transit. You earn 1 point per $1 on all your other everyday purchases.

These points can be redeemed against any travel purchase at a rate of 1,000 points = $10 (flights, hotels, all-inclusives and even Airbnb), or as cash back with Scene+ at the same rate.

The Scotiabank Passport Visa Infinite +* Card also offers:

  • No fees for foreign currency transactions
  • 6 complimentary airport VIP lounge passes
  • Excellent insurance for your travels and purchases
  • Visa Infinite* Concierge Services

We have named this credit card the Best Credit Card with No Foreign Transaction Fees in 2024, 2025, and 2026.

Annual fee

Primary card$150
Additional card$50

Annual income required

Individual$60,000
Household$100,000

Conversion fees

0%

Earning rate

  • 2xGroceries
  • 2xRestaurants
  • 2xTransit
  • 2xEntertainment
  • 1xAll spending

Value

1st Year Value$650
2nd Year Value$397

Card benefits

Concierge service24/7
Airport lounge access$240

Travel insurance

Travel medical (under 55)Up to $1,000,000 / 25 days
Travel medical (55-64)Up to $1,000,000 / 25 days
Travel medical (65+)Up to $1,000,000 / 3 days
Trip CancellationUp to $1,500
Trip InterruptionUp to $2,500
Delayed BaggageUp to $1,000
Lost BaggageUp to $1,000
Flight DelayUp to $500
Hotel BurglaryUp to $1,000
Travel AccidentUp to $500,000

Purchase protection

Purchase ProtectionIncluded
Extended Warranty+1 years
Auto Rental CollisionUp to $65,000 / 48 days

Which credit card should you choose for travel?

If you travel regularly, the credit card you carry makes a real difference: travel insurance, points earning, airport lounge access and no foreign exchange fees. Use our credit card comparator to filter through 200+ Canadian cards based on your needs, or browse the best credit cards in Canada, ranked monthly by the Milesopedia team.

Other useful flight tools

GCMap – Frequently Asked Questions

Is Great Circle Mapper free?

Yes. Great Circle Mapper is completely free and requires no sign-up. You simply enter airport codes in the search bar to get distances and a map.

Why calculate a flight distance with GCMap?

Several loyalty programs, such as the British Airways Executive Club (Avios), price a flight in points based on the distance flown. Knowing the exact distance helps you spot the best point redemptions and the most advantageous stopovers.

What are the four characters to know on GCMap?

The dash (-) links destinations, the comma (,) separates queries, the slash (/) duplicates a query, and the at sign (@) draws a radius from an airport. These four characters cover most maps.

Does GCMap show the actual flight path?

GCMap draws the great-circle route, the shortest distance between two points on the globe. The actual flight path can vary slightly with air corridors, but the difference is minimal for estimating points.

Our featured card

Featured
Annual fee
$120
Our valuation
$990

Milesopedia first-year estimateFirst-year valueWelcome bonus$990Total$990Rewards on your spending are not included. The calculator that adds them from your own profile is on the card's page.

Welcome offer
Up to 110,000 points

Ends Sep 22, 2026

Apply Now

on American Express's website

Apply with confidence — no impact on your credit scoreApply with confidenceCheck whether your application will be approved before you submit it, with no impact on your credit score*When you apply for a personal American Express Credit Card, we will tell you whether you are eligible without affecting your credit score. So you can apply with confidence.*Instant decisions are only available for consumer Card applications (also called “personal Cards”).

The Marriott Bonvoy® American Express®* Card is the best credit card in Canada for free hotel nights.

New Cardmembers can earn up to 110,000 Marriott Bonvoy® points with the current offer:

  • Earn 80,000 points after you spend $6,000 on your Card in your first 6 months of Cardmembership.
  • Plus, earn 30,000 points by making a purchase during your 15th month of Cardmembership.

This offer ends on September 22, 2026. The annual fee is $120, and there is no annual fee on Additional Cards, so you can add a partner or a family member at no extra cost.

Every year after your first Card anniversary, you receive an Annual Free Night Award good for a redemption of up to 35,000 points at eligible hotels and resorts worldwide. At a valuation of 0.9 cents per Marriott Bonvoy point, that certificate is worth roughly $315, which on its own more than covers the $120 annual fee. That is the main reason to keep this Card year after year instead of cancelling it.

To get the most out of the certificate, aim it at a night that would otherwise price close to the 35,000 point ceiling.

The Card also gives you 15 Elite Night Credits each calendar year and automatic Marriott Bonvoy Silver Elite status. Those credits count toward the next Elite tier, so you begin every year 15 nights ahead of where you would otherwise start.

You move up to Gold Elite status automatically when you reach $30,000 in purchases on the Card in a year, or when you combine 10 qualifying paid nights within one calendar year with the 15 Elite Night Credits from your Card.

Marriott Bonvoy points are generally valued at 0.9 cents each. On that basis, the 110,000 point welcome offer is worth about $990, and an Annual Free Night Award used at its full 35,000 point ceiling is worth about $315.

Marriott Bonvoy points pull their weight on free nights rather than on gift cards or merchandise, which is why this Card should be judged on the hotel stays it produces.

You earn 5 points per dollar on eligible purchases at participating Marriott Bonvoy hotels and 2 points per dollar on all other purchases. Points can be redeemed for free nights with no blackout dates at more than 7,000 hotels around the world.

The Card carries a solid package of coverages: $500,000 travel accident insurance, flight delay, baggage delay, lost or stolen baggage and hotel or motel burglary at $500 each, car rental theft and damage up to $85,000 for rentals of up to 48 days, Purchase Protection for 90 days and a one year Extended Warranty.

Two things to plan around: the 2.5% foreign transaction fee on purchases made in a foreign currency, and the 21.99% purchase interest rate, which makes this a Card to pay in full every month. Like all American Express Canada Cards, no minimum income is published for this Card, and you can see whether you would be approved before you apply, with no impact on your credit score.

Annual fee

Primary card$120
Additional card$0

Annual income required

Individual$0
Household$0

Conversion fees

2.5%

Earning rate

  • 5xMarriott Bonvoy hotels
  • 2xAll spending

Value

1st Year Value$1,437
2nd Year Value$312

Travel insurance

Delayed BaggageUp to $500
Lost BaggageUp to $500
Flight DelayUp to $500
Hotel BurglaryUp to $500
Travel AccidentUp to $500,000

Purchase protection

Purchase ProtectionIncluded
Extended Warranty+1 years
Auto Rental Collision (primary)Up to $85,000 / 48 days

Our editorial integrity

Our reviews and rankings are based on an objective assessment. Advertisers do not influence our content. We may receive compensation through some links; our analysis and opinions remain independent.