The A-Side & B-Side:
Building Duolingo to 200M Users

Gina Gotthilf

Co-founder & COO, Latitude
Former Head of Growth, Duolingo

2024

Philosophy

Every Life Has An A-Side & B-Side

"Most of us have a lot of B-moments every day, every week, every month. It's easy to think things aren't going to work out for us because we're in one of those B-moments, if we don't recognize them as moments."

Your A-side is what you show the world: the wins, the Instagrammable highlights
Your B-side is where the real work happens: the failures, pivots, and persistence
Both are essential. Recognizing B-moments as temporary is key to resilience
Career is long. You have time to figure it out. Don't stress the pace

The Duolingo Playbook

How Brand + Product = Viral Growth

200M

monthly active users

starting users

66x

growth from mission

Mission first: "Free language education for the world" is bigger than "download an app"
Brand voice: Playful, unexpected, quirky, never generic. The owl has personality.
One post a week: Share data proving effectiveness. Make the mission visible in every channel
Testing everything: A/B tested sad owl's tears, notification copy, paywall messaging
PR is organic: A lovable brand gets reporters to write stories without you asking

Gina's insightCommunication isn't about conveying a message. It's about conveying it so the listener receives it, understands it, and remembers it.

Organic Growth

What Actually Works (Without Paid)

Product-led growth: A/B testing and data science are organic growth. They're free growth channels.
Copywriting matters: Test your paywall message. "By paying, you make language accessible to millions" moved the needle.
Brand cohesion: Every notification, email, screen should feel like Duolingo. Could another company write this? If yes, rewrite it.
Mission in product: The mission of accessibility affects conversion rates. People pay for the mission, not just the feature.

Failed test

Posting team photos on Facebook with "behind the scenes" captions. No one cared. Lesson: Don't confuse internal stories with external resonance.

Passive-aggressive genius

The "This doesn't seem to be working" notification after 5 days of inactivity became a meme. It's Duolingo's voice and it drives retention.

Voice & Copy

Build a Unique Voice

Ask of every piece of copy: "Could this be written by another company?"
If yes, rewrite it until it can't be.
Define the voice explicitly: tone, words, what's too much, what's too little
Hire for brand fit. New hires won't naturally write in your style, train them
Quirk + humor + self-deprecation = people feel it, share it, remember it

The owl effectPersonality in product is a growth lever. Duolingo's tone of voice became its most defensible asset and its strongest acquisition channel.

Contrarian

Growth Myths (That Are Wrong)

✗You need a huge paid budget to grow fastINSTEAD →✓ Organic + brand + product > paid. Duolingo grew 200M users mostly without paid ads.

✗Brand is a luxury, growth is coreINSTEAD →✓ Brand IS growth. A lovable brand multiplies everything: retention, referrals, PR.

✗PR and marketing are nice-to-havesINSTEAD →✓ PR is the highest-leverage channel. A good story beats paid ads 100x over.

✗Failure means you're on the wrong pathINSTEAD →✓ Your B-side is where the learning lives. Recognize it as a phase, not an ending.

Based on Gina Gotthilf's episode on Lenny's Podcast. All ideas on this page are from the episode.Watch on YouTube Follow @ginag on X

GO DEEPER IN THE EPISODE

04:34 The Vamos Latam Summit 07:22 Gina’s “A and B sides” framework 09:34 Her B side 16:27 Lessons from working on Mike Bloomberg’s presidential campaign 20:40 How Gina was able to 3x the conversion rate on a campaign site in one day 24:34 4 areas Duolingo leaned into to have success in the difficult world of B2C subscriptions 36:39 B-side lessons from Duolingo 42:05 The importance of trusting your gut 44:54 Organic growth tactics and the importance of branding 48:01 What makes for remarkable branding 52:01 Duolingo’s process for keeping copy on-brand 52:45 How Duo’s passive-aggressive messages led to a movement 55:19 How Latitud uses niche humor as part of their branding 56:31 Duolingo’s TikTok 59:02 Lessons from internationalizing Duolingo 1:03:51 Why Gina was drawn to the tech industry in Latin America 1:09:26 What Latitud does 1:17:20 Opportunities in emerging markets 1:20:45 Lightning round

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