How Big Is the Island of Oahu? (Size Comparisons with States & Cities) (2024)

Oahu, the vibrant and widely visited Hawaiian island, boasts the distinction of being home to the state capital, Honolulu.

However, the island’s actual size often leaves people wondering about its dimensions, as its remote location makes it challenging to gauge.

Understanding the scale of Oahu is crucial in order to grasp its geography and plan your island explorations more effectively.

To provide you with a comprehensive perspective, I will delve into the island’s dimensions and offer meaningful comparisons to enhance your understanding of its size.

How big is the island of Oahu?

The island of Oahu is approximately 597 square miles (1,545 square kilometers) in size, including small associated islands such as Ford Island plus those in Kāneʻohe Bay and off the eastern (windward) coast, making it the 20th-largest island in the United States.

As far as length and width goes, Oahu is 44 miles (71 km) long and 30 miles (48 km) wide and its shoreline is 227 miles (365 km) long. In other words, it’s about the length of the Panama Canal.

How does Oahu measure up to other Hawaiian Islands?

In terms of how Oahu stacks up to the other Hawaiian islands, it is the third largest Hawaiian island, following the Big Island (Hawaii) and Maui.

Even though some believe Kauai to be one of the much smaller Hawaiian islands, Kauai and Oahu are actually very similar in size in terms of land area. Kauai is 552 square miles, which means that Oahu is only about 8% larger than Kauai.

But the Big Island is much larger than Oahu, coming in at 4,028 square miles. This means that the Big Island is about 6.7 times larger than Oahu.

The Big Island is also much taller than Oahu. The highest point on the Big Island is Mauna Kea, which is 13,803 feet tall. The highest point on Oahu is Ka’ala, which is 1,023 feet tall.

In terms of population, Oahu blows the other islands out of the water. The Big Island has about 190,000 people, while Oahu has about 980,000 people. This means that Oahu is about 5 times more populous than the Big Island. On the other hand, Kauai has a population of approximately 73,000 people, making Oahu roughly 13 times more populous than Kauai.

This much higher population is relevant to your travels around Oahu because in some places it can mean dealing with a lot more traffic both on the road and when trying to get around on foot, waiting in lines, etc.

Generally, if you want to get away from the throngs of tourists and urbanization, you don’t go to Oahu, or at least not Honolulu.

How does Oahu measure up to other US states?

If you’re curious to compare Oahu with other states, here are some intriguing details. Oahu spans approximately half the size of Rhode Island, which covers 1,214 square miles.

In contrast, Texas encompasses a vast area of 268,596 square miles, making it roughly 450 times larger than Oahu.

But now let’s take a look at the size comparison of Oahu and different regions and cities of the US, starting off with another tropical area of the US: the sunny Florida Keys

The Florida Keys, while a completely different shape (a string of islands), are about 137 square miles, meaning that the Florida Keys are about 4.2 times smaller than Oahu, although they stretch over 150 miles farther!

What about lakes in the US?

Well, Oahu is much smaller than the biggest lake in the USA, Lake Superior, as Lake Superior is 31,700 square miles. This means that Lake Superior is about 53 times larger than Oahu in terms of land area!

One lake in the USA that is approximately 597 square miles in size is Louisiana’s Lake Pontchartrain, which is about 630 square miles. So you could theoretically fit Oahu inside the body of water just north of New Orleans.

What about regions?

Oahu is almost the exact size of Cape Cod Bay (604 square miles) meaning that Oahu could snugly fit inside of the hook-shaped peninsula.

And as for cities?

New York City, is about 304 square miles which means that Oahu is roughly twice the size of New York City. Houston, Texas, has a land area of665 square miles (some say closer to 600), making it a very close fit for the island of Oahu.

The biggest county in the US, Los Angeles County, is about 4,058 square miles putting Los Angeles County about 6.8 times larger than Oahu in terms of land area.

How long does it take to drive around Oahu?

Contrary to what many think, you cannot drive around the entire island of Oahu because there is no road that completely encircles the island.

Instead, you can only drive along a portion of the island. Typically, when people talk about driving around the island they mean doing the “Eastern Loop” that runs along the stunning Kamehameha Highway (Route 83).

They then come down the center of the island because there is a small peninsula called Kaena Point that juts out into the Pacific Ocean on the northerwest shore which breaks up the continuity of an encircling highway route.

If you start in Waikiki, you can drive the ~110-mile loop around the eastern half of the island in about 3 hours and 30 minutes without stopping much, as shown by the map below.

If you wanted to hit up the northern coast and western side of the island it would take about 5 to 6 hours, depending on traffic. Basically, you would be spending the entire day just driving around the island and you’d have to do some backtracking on the west side.

The time estimations above assume that you make very few stops along the way.

The thing is, there are so many interesting sites to see along these highways!

From the beautiful landscapes of Kualoa Ranch to Pearl Harbor, and all of the beaches and waterfalls in between, you’ll likely want to stop a lot along the way.

So if you do plan on driving around the island of Oahu, I’d just go ahead and plan for that to be an all day event so that you can really enjoy some of the sites and make plenty of worthwhile stops along the way.

Final word

I hope this article has provided you with a better understanding of the size of Oahu.

Comparing it to familiar areas can indeed help in visualizing the island and anticipating what it will be like to navigate and explore. Having a sense of scale can also contribute to a more informed and enjoyable experience as you move around the captivating island of Oahu.