If you’ve ever binged How I Met Your Mother or revisited the Sunnydale High hallways in Buffy the Vampire Slayer, you’ve probably noticed something kind of funny about Lily Aldrin or Willow Rosenberg. She looks tiny. Like, "standing on a soapbox to reach the microphone" tiny. But if you actually dig into the numbers, you'll find that the "short" friend in every iconic sitcom group isn't actually as small as the camera makes her out to be.
Honestly, the confusion around how tall is Alyson Hannigan mostly comes down to the people she stands next to. When you spend nine years playing the wife of Jason Segel—who is a literal giant at 6'4"—you’re going to look like a hobbit by comparison. It’s basically a perspective trick that’s fooled us for decades.
The Real Numbers Behind the Height
Let's get the stats out of the way first. Alyson Hannigan is officially 5 feet 5 inches tall (that's about 165 cm for the metric fans).
Now, I know what you’re thinking. "Wait, she’s 5'5"?" That is actually the exact average height for an American woman. She isn't short. She isn't tall. She is perfectly, mathematically middle-of-the-road. Yet, in the cultural zeitgeist, she’s often categorized with the "tiny" actresses like Kristin Chenoweth or Hayden Panettiere.
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Why? Because Hollywood casting is a game of extremes.
The Marshall Eriksen Effect
In How I Met Your Mother, the height gap between Lily and Marshall was a recurring visual gag. Jason Segel towers over her by nearly a full foot. When they stood side-by-side, the producers frequently had to get creative with framing. You’ve probably noticed that in many scenes where they are walking and talking, the camera stays tight on their faces, or she’s wearing massive heels. If she wasn't in four-inch pumps, she’d be buried in his armpit.
It wasn't just Jason, either. Cobie Smulders, who played Robin Scherbatsky, stands at 5'8". Neil Patrick Harris is about 6'0", and Josh Radnor is around 5'10". When you are the only 5'5" person in a room where the average height is nearly 6 feet, you become "the short one" by default.
Looking Back at the Buffy Days
If you go back even further to her breakout role as Willow Rosenberg in Buffy the Vampire Slayer, the height dynamics were totally different. This is where it gets interesting.
Sarah Michelle Gellar, the Slayer herself, is actually only about 5'3" or 5'4". If you watch closely during the early seasons, Willow is noticeably taller than Buffy. But because Willow’s character started out so meek and "mousy," our brains projected a smaller stature onto her. We associate shyness with being small. It’s a weird psychological thing we do.
By the time she reached the American Pie era, she was often paired with actors like Jason Biggs (5'9"), making her look much more "normal-sized" on screen.
The Wardrobe Magic and "Apple Boxes"
In the industry, they use these wooden crates called "apple boxes" to level out actors during close-up shots. It’s common knowledge that Hannigan spent a fair amount of time on these during her HIMYM years.
There’s a legendary story among fans about how the crew had to find ways to make Lily look like she could realistically kiss Marshall without him throwing out his back every time. This usually meant Alyson was rocking some of the most uncomfortable, towering heels known to man. If you look at her footwear in the show, she’s rarely in flats unless she’s sitting on the "big yellow couch."
Comparison Table: The HIMYM Cast Heights
| Actor | Height (ft/in) | Height (cm) |
|---|---|---|
| Jason Segel | 6'4" | 193 cm |
| Cobie Smulders | 5'8" | 173 cm |
| Neil Patrick Harris | 6'0" | 183 cm |
| Josh Radnor | 5'10" | 178 cm |
| Alyson Hannigan | 5'5" | 165 cm |
Does It Actually Matter?
Kinda. In Hollywood, height can dictate the types of roles you get. For Alyson, being 5'5" gave her the "girl next door" versatility. She was tall enough to play a lead, but short enough to play the "adorable" best friend.
But honestly, the obsession with her height is more about her energy. She has this "small but mighty" vibe. Whether she’s playing a powerful witch ending the world or a kindergarten teacher with a shopping addiction, she commands the space.
It’s also worth noting that height is one of those things that people lie about constantly on the internet. You’ll see some sites claiming she’s 5'4" and others saying she’s nearly 5'6". The consensus from reputable talent databases and her own past interviews settles comfortably at that 5'5" mark.
What We Can Learn From the "Short" Willow
If you're ever feeling "short" in your own life, just remember that perception is everything. You might be the average height for a human being, but if you hang out with basketball players, you’re going to look tiny.
The takeaway here? Don't trust your eyes when you're watching TV. Between camera angles, "Manolo Blahniks," and wooden boxes, Hollywood is basically a house of mirrors. Alyson Hannigan isn't some petite pixie; she’s a totally average-height woman who just happened to spend a decade standing next to a mountain of a man named Jason.
To get a real sense of her stature without the sitcom filters, look at her red carpet photos where she's standing solo or with her husband, Alexis Denisof (who is about 6'2"). You'll see that while she's definitely shorter than him, she holds her own just fine.
Next time you're watching a HIMYM rerun, keep an eye on Lily's shoes. You'll start to notice the platform sneakers and the 5-inch stilettos that were doing the heavy lifting to bridge that 11-inch gap with Marshall. It's a fun game to play once you know the secret.
Check out some of her more recent appearances on Penn & Teller: Fool Us to see her standing next to a wider variety of people. It’s the best way to see the "real" 5'5" Alyson without the "Lily and Marshall" height distortion.