Codédex turned learning to code into a game, and $81K in monthly revenue

This story is based on public sources: verified revenue on TrustMRR, Codédex's website and Sonny Li's public profile on X. It is not an interview. Revenue figures were last checked on 3 November 2026.

Most coding courses compete on content. Codédex competes on fun. Its tagline is "Start your coding adventure", and it treats lessons like levels in a game. The verified numbers suggest the approach works.

The numbers

On TrustMRR, Codédex shows $81,237 in MRR from 6,482 active subscriptions, verified with a Stripe API key. All-time revenue is $1,508,237, and revenue in the last 30 days was $62,964. It ranks 23rd by MRR on TrustMRR's homepage leaderboard, with 5% month-over-month growth.

The company was founded in November 2022 in the United States. TrustMRR lists roughly 2,000,000 users. That matches the Codédex X account bio, which says "Join 2m learners" and places the company in Brooklyn, New York.

A generous free tier

The business model is a classic freemium funnel, with an unusually large free layer. According to the listing, the free plan includes more than 250 hours of interactive coding lessons. The paid Club membership starts at $9.99 a month.

That math only works at volume. Two million learners and about 6,500 paying subscribers implies a small conversion rate. That is common for consumer education, where most learners never pay. What matters is that the free product is good enough to keep pulling people in, and the paid tier is cheap enough that the committed ones upgrade without much thought.

A teacher's product

Founder Sonny Li describes himself on X as "building @codedex_io" and "lvling up the next generation of technologists". His bio also notes that he "taught CS at columbia & nyu".

That background is visible in the product. TrustMRR lists the problem Codédex solves as providing "a fun, interactive, and beginner-friendly way to learn coding". The target audience is "beginner coders and individuals looking to transition into tech careers". Those are the students a computer science instructor meets in the first week of an intro class, before many of them give up.

Codédex's newer positioning shows the moment it is in. Its X bio now leads with "Build what AI can't". As AI tools write more code, coding education has to answer a harder question about why beginners should learn at all. Codédex's answer, for now, is to make learning feel like play, and to keep it free until people want more.

Small team, lean stack

TrustMRR lists the stack as TypeScript and React on the front end, with Vercel, Google Cloud and Stripe on the back end. The listing shows about 20,800 lines of code, which works out to roughly $72 in revenue per line.

Why it matters

Edtech is often treated as a venture-scale category, with heavy marketing spend and content teams. Codédex shows a different path. It has a big free product, a low-priced membership, and a founder who taught the subject for years. The result is more than $1.5 million in verified revenue since 2022.

Sources

1. TrustMRR, Codédex. trustmrr.com/startup/codedex
2. Codédex on X. x.com/codedex_io
3. Sonny Li on X. x.com/sonnynomnom
4. Codédex website. codedex.io