Great Loop Calculator

The Great Loop is about 6,000 statute miles long. America’s Great Loop Cruisers’ Association (AGLCA) puts the shortest route at about 5,250 statute miles and says most Loopers report a trip of about 6,000 miles once they add route choices and side trips. Enter your cruising speed, the hours you run each day and how often you cruise to see the hours underway, the cruising days, the calendar time and the fuel for your Loop.

How Long Does the Great Loop Take?

Traditionally about a year. AGLCA notes that the Loop has been done in as little as 12 days and in as much as 12 years, that it is a seasonal trip, and that more Loopers now cruise it in segments of a few weeks or months, going home in between.

Two AGLCA averages make a good starting point: most Loopers average about 50 miles a day, and most cruise one day in every three. The calculator starts there: 10 mph for 5 hours is a 50-mile day, and 10 cruising days a month is about one day in three. At those settings a 6,000-mile Loop is 600 hours underway, or 120 cruising days, which takes 12 months. The 5,250-mile minimum route takes 525 hours, 105 cruising days and 10.5 months.

Speed	Hours	Cruising days	Months
6 mph (5.2 kn)	1,000	200	20
8 mph (7 kn)	750	150	15
10 mph (8.7 kn)	600	120	12
15 mph (13 kn)	400	80	8
20 mph (17 kn)	300	60	6

The table is for a 6,000-mile Loop at 5 hours a day and 10 cruising days a month: hours underway, cruising days and calendar months. Calendar time spreads your cruising days at the pace you enter and adds nothing else, so choose a pace that leaves room for weather days, repairs and longer stays, and add side trips to the route length.

How the Great Loop Calculator Works

The plan rests on these assumptions:

• One average speed for the whole route. Currents, no-wake zones and locks make the real speed vary from leg to leg.
• The same hours underway on every cruising day; the last day can be shorter.
• Cruising days spread evenly at the pace you enter. A week is 7 days and a month 30.4 days, an average month (365.25 days ÷ 12).
• The route length is a typical figure, 6,000 miles from AGLCA, or the number you enter. The calculator doesn’t measure a route.
• Fuel is burned at the same rate for every hour underway, with no reserve and nothing for idling, a generator, current or weather.
• No seasons. Canal opening dates, hurricane season and marinas that close for winter aren’t in the plan; the seasons section below covers them.

AGLCA gives the Loop’s length in statute miles, so the calculator works in miles. If you know your cruising speed in knots, choose Knots and it converts the speed for you (1 knot is about 1.151 mph); the MPH to Knots Converter converts speeds both ways. To turn the route length into nautical miles, use the Miles to Nautical Miles Converter: 6,000 statute miles is about 5,214 nautical miles.

Great Loop Fuel Cost

Fuel is your hours underway times your boat’s fuel burn. With example values of 8 gallons an hour and $6.00 a gallon, the 600 hours of a 6,000-mile Loop at 10 mph burn 4,800 gallons, which cost $28,800. Use your own burn at your cruising speed and current fuel prices: both change the total a lot.

Range matters as much as the total. AGLCA lists the stretch from Alton, Illinois, on the Upper Mississippi to Paducah, Kentucky, about 240 miles, as the longest run on the Loop without a fuel stop, and some Loopers whose boats lack the range carry extra fuel in cans, drums or bladders on deck. At 10 mph and 8 gallons an hour, 240 miles takes 192 gallons before any reserve. For the fuel on a single leg, use the Boat Fuel Calculator.

What Is the Great Loop?

The Great Loop is a circumnavigation of the eastern United States and part of Canada that boaters, called Loopers, make aboard their own boats, mostly on protected inland waterways. AGLCA lists these as the primary waterways of the basic route, in the usual counterclockwise order from Florida:

• The Atlantic Intracoastal Waterway, the Chesapeake Bay and the C&D Canal
• The Atlantic Ocean from Cape May to New York Harbor (or inland waterways through part of New Jersey)
• The Hudson River, the Erie Canal and the Oswego Canal to Lake Ontario (or the Erie Canal west to Lake Erie, or the Triangle Loop through Lake Champlain)
• The Trent-Severn Waterway in Canada, Georgian Bay, Lake Huron and Lake Michigan
• The Illinois, Mississippi, Ohio and Tennessee rivers and the Tenn-Tom Waterway to Mobile Bay
• The Gulf Intracoastal Waterway and the Okeechobee Waterway (or the Gulf Intracoastal on to the Keys)

Several stretches have choices, and your boat’s height decides some of them; AGLCA’s interactive map shows the options.

When to Cruise Each Part of the Loop

The Loop follows the seasons. AGLCA’s advice is to be on the northern part of the route in the warm summer months, on the inland rivers in the fall and in Florida for the winter, then to follow the warm weather north up the East Coast in the spring:

• Spring: Florida, Georgia and the Carolinas, leaving before hurricane season starts on June 1 and reaching Norfolk, Virginia, at the end of the Atlantic Intracoastal Waterway, by early May. For the Chesapeake, AGLCA’s phrase is “May in the Bay.”
• Early summer: the New York canals. The New York State Canal Corporation announces the Erie Canal’s schedule each year; it usually opens in mid-May, so AGLCA suggests arriving no earlier than late May. For 2026 the Canal Corporation scheduled the whole canal system to open on May 15 and stay open until October 14.
• Summer: the Trent-Severn Waterway and Georgian Bay in Canada, then Lakes Huron and Michigan, leaving Chicago in September after Labor Day and no later than early October, when marinas begin to close.
• Fall: the inland rivers, aiming for Mobile Bay in November. Hurricane season runs through November 30, and your insurance policy may set when you can enter the Gulf.
• Winter: the Gulf Coast of Florida.

The Loop is usually cruised counterclockwise, AGLCA says, so that you run with the current on most of the inland rivers and, on a one-year trip, stay on the Great Lakes and rivers during hurricane season. You can start anywhere, but where you start sets the time to leave: from Chicago, for example, you would start in the fall to reach Florida before winter.

Boat Limits on the Great Loop

The calculator doesn’t check whether your boat fits the route. AGLCA’s FAQ (read Oct 21, 2026) lists these limits, and Parks Canada gives the figures for the Trent-Severn Waterway:

• Height above the water (air draft): AGLCA says the lowest fixed bridge you can’t avoid is charted at 19.6 feet, at mile 300.6 on the Illinois River. In New York, the Erie and Oswego canals to Lake Ontario need 21 feet of clearance, the Triangle Loop through Lake Champlain and the St. Lawrence 17 feet, and the Erie Canal west to Lake Erie 15 feet. Leaving Lake Michigan, the Chicago River through downtown needs 17 feet; otherwise you take the Cal-Sag Canal south of Chicago.
• Depth (draft): AGLCA recommends a draft not much more than 5 feet. On the Trent-Severn, Parks Canada gives about 8 feet (2.4 m) of water in the channel from Trenton to Peterborough and about 6 feet (1.8 m) from Peterborough to Port Severn, warns that depths are not guaranteed and can be less in a few places, and asks the operator of any boat drawing 5 feet (1.5 m) or more to call the waterway’s office first. AGLCA adds that boats drawing more than 5 feet must sign a waiver. There are routes around it.
• Length and width: AGLCA knows of no practical length limit. On the Trent-Severn, Lock 45 at Port Severn is the smallest lock, 84 feet long and 23 feet wide (25.6 by 7.0 m), and Parks Canada says its length limits the size of boat that can go through the whole waterway.
• Fuel range: about 240 miles between Alton, Illinois, and Paducah, Kentucky.

Water levels, closures and clearances change, so check current charts, Local Notices to Mariners and lock schedules before each leg; this page doesn’t certify any route or boat. NOAA’s electronic navigational charts cover U.S. coastal waters and the Great Lakes, and the U.S. Army Corps of Engineers publishes Inland ENCs for many U.S. rivers. Our guide How to Read a Nautical Chart explains charted depths and clearances.

Plan Each Leg

For a single leg, the Boat Travel Time Calculator finds the distance over water between two points you pick on the map, or takes a distance you already know, and the time at your cruising speed. The Speed, Distance and Time Calculator adds an arrival time. Before you leave, give a float plan to someone ashore: the Float Plan Generator makes one you can print, copy or download.

Frequently Asked Questions

Sources

• America’s Great Loop Cruisers’ Association, Great Loop FAQs and home page (read Oct 21, 2026): route length, waterways, timing, seasons, direction and boat limits.
• Parks Canada, Trent-Severn Waterway technical data (updated Nov 19, 2022) and Lock 45, Port Severn (updated Sep 1, 2026), both read Oct 21, 2026: channel depths and the size of the smallest lock.
• New York State Canal Corporation, 2026 Navigation Season notice to mariners (Jan 20, 2026; read Oct 21, 2026): the 2026 opening and closing dates.
• NOAA Office of Coast Survey, NOAA ENC (read Oct 21, 2026): electronic chart coverage and the Army Corps of Engineers’ Inland ENCs.