Solopreneur case studies
A solopreneur is someone who runs a business without hiring employees. Small Start records one-person and side-project businesses only: monthly revenue, profit, acquisition channels and hours invested, each with a source.
One-person businesses share a design: no fixed costs, automated support, and distribution that runs on search or a marketplace. Each case breaks that design down with numbers.
- Case studies
- 201
- Sale price
- 10億円
Solopreneur and side-business cases
1–24 of 201
CyberLeads: After 19 Failed Projects, a "Freshly Funded Companies" Lead List Built in 31 Days Now Makes $53.7K/Month — with a Free Newsletter as the Sales Engine
Greek developer Alex West launched CyberLeads in February 2020 — his 20th project after 19 failures, built in 31 days. It sells monthly lists of freshly funded companies. From $290 MRR in month one to $53.7K/month by October 2024, with a free 10-lead weekly newsletter funneling buyers to the paid tiers.
Sauna Ikitai: A Hobby Search Site Reaches ¥72.88M in Year-Two Revenue — Zero Employees and a ¥370/Month Subscription Capped at 10,000 Members
Sauna Ikitai, a sauna search site four enthusiasts started as a hobby, grew from about ¥14.01M in first-year revenue to about ¥72.88M with over ¥10M in net profit in year two, per reporting based on its statutory filings. No employees were hired, and the ¥370/month paid membership is capped at 10,000 members. The endpoint of turning a hobby into a business, read in numbers.
Feather: The "Write in Notion, Publish as a Blog" SaaS Sold for $250K Two Years In — the Buyer Was Tibo, Who Exited Tweet Hunter
Bhanu Teja P built Feather in public on X, reaching $50K ARR 9.5 months after launch. In June 2024 it sold for $250K at $6K MRR — roughly 3.5x annual revenue. The buyer was Tibo, known for exiting Tweet Hunter. A rare look at how peer-to-peer micro-M&A gets priced.
SEObot: An AI That Writes SEO Articles Hits $46K MRR and $1.8M Lifetime — the Numbers Come from a Public Stripe-Linked Dashboard
John Rush's SEObot is a SaaS where AI keeps writing SEO articles. As of August 2026, its $46,517 MRR, $1.82M lifetime revenue, and 636 subscriptions are verifiable by anyone on a Stripe-connected public dashboard. Reading the numbers, AI-content controversy and all.
GummySearch: The Reddit Research SaaS That Chose to Close While Profitable — Four Years Ended by a Commercial API License That Never Came
After roughly four years running his Reddit research tool alone, founder Fed shut GummySearch down in November 2025 when commercial-license negotiations over the Data API fell through. Failory reported $35K MRR at closure. With 140,000 users and the business in the black, this was an ending caused by neither churn nor running out of money.
The God of Blog: 310K Pageviews Made ¥47K a Month, 6,499 Pageviews Made ¥53K — a 6-Year-2-Month Measured Record of Niche Selection
A One Piece analysis blog earned ¥46,801 on 310K monthly pageviews; the third blog, about blogging itself, earns ¥53,232 on 6,499. Per-pageview value of ¥0.15 versus ¥8.2 — Hebo published the full 6 years 2 months it took to reach ¥50K a month, failed sites' numbers included.
BoltAI: $15K a Month on One-Time Licenses in a Subscription-Only AI Market
Vietnamese solo developer Daniel Nguyen went against the "AI tools = subscriptions" consensus and sells BoltAI, a native macOS AI app, as a one-time license: an average of $15K a month and 7,000 customers 18 months after launch. He also documented the $19→$79 price climb and the year lost on his failed first product, KTool.
The Exit 8: A ¥470 Solo-Developed Game That Sold 30,000 Copies on Day One and 1.4 Million in Just Over a Year — How "Spot the Anomaly" Made Streaming Sell Copies
The Exit 8, a ¥470 walking simulator built alone by a former game-company employee, sold over 30,000 copies on launch day in November 2023 and passed 1.4 million worldwide by January 2025. It spawned the "8-like" genre, and its live-action film adaptation reached ¥5.17 billion at the box office.
ProjectionLab: $1M ARR from 4–6 Hours a Night, Every Weeknight, for 4 Years — the Growth Curve of a Financial-Planning SaaS Raised by the FIRE Community
ProjectionLab started at $150 MRR in 2021 and reached $1M ARR in June 2025. Developer Kyle Nolan quit his job only at $23K MRR. A Hacker News post, one word from Mr. Money Mustache, and an 8,500-member Discord were the main engines of growth.
Inkdrop: ¥150,000 a Month from a $4.99 Markdown Note App — Two Years of an Indie SaaS That Stopped PR Emails and Refused to Go Freemium
Japanese developer TAKUYA's Inkdrop reached ¥150,000 in monthly sales about two years after launch, with a ¥950,000 single-month spike in August 2019. A 1,000-person private beta, a 60-day free trial, no freemium, no more PR emails — the reasoning behind each decision is public, alongside the numbers.
Skeb: The "Personal Hobby Service" That Sold All Its Shares for ¥1 Billion — Settling the Risk of One Person Holding ¥200 Million a Month in Transactions
Skeb, which its founder called a "personal hobby service," reached 1 million registered users and roughly ¥200 million in monthly transaction volume in just over two years, then became a subsidiary of Jitsugyo no Nihon Sha in February 2021 for ¥1 billion. The top reason for selling was not stalled growth but payment-settlement risk.
Leadverse Gets All Its Customers From Reddit, and 90% of Its Costs Are LLM Fees — $3,300 MRR Built Between a Day Job and a Newborn
Leadverse, an AI tool that finds prospects on social media, reached $3,300 MRR and 130+ paying customers ten months after launch. Every dollar of revenue comes from Reddit, and LLM API fees make up about 90% of operating costs.
AI Directories: $10,000 a Month from One-Time Purchases, Built on a Chore He Automated
A service that submits AI products to 100+ directories by hand. Built for the founder's own use, it became the biggest earner in his portfolio, now at $10,000/month across products. But the three numbers he publishes — interview, pricing page, revenue page — don't match.
Questgen & Supermeme Today: 2.5 Million Signups, $6,500–7,000 a Month — Three AI Tools Down From a $100K Peak Year
Three AI tools run by a data scientist alongside his day job. Combined signups exceed 2.5 million, yet current monthly revenue is $6,500–7,000 — down from the 2025 peak of $100K a year.
Abbey Road: He Sold His Own Assets to Take Over a 20-Year Rakuten Watchband Store
Katsuhito Saiki, who worked at a seafood trading company, took over "Abbey Road," a watchband shop that had run for 20+ years on Rakuten Market. He'd once passed on the listing because it exceeded his budget, but returned to it; when a loan from the Japan Finance Corporation was rejected, he sold off his own assets to raise funds. Negotiations spanned about 1 year and 8 months.
Is a coin laundry passive income? ¥150,000-500,000 a month, 7-10 year payback — an owner's numbers
A current owner running a coin laundry as a side business published their income statement: initial investment of ¥13-22 million, monthly revenue of ¥150,000-500,000, fixed costs of ¥250,000-530,000, take-home of a few tens of thousands to over ¥100,000 per month, with a 7-10 year payback period. We examine content in which the operator personally dismantles the "passive income" image.
manablog at ¥1,000,000–1,500,000/month, and two sites left idle 3–4 years before closing — the numbers Manabu published under his real name
manablog earns ¥1,000,000–1,500,000/month at 500,000 PV, with one article alone worth roughly ¥500,000/month, while two other sites earning ¥100,000–150,000/month closed after 3–4 years of neglect.
Lenny’s Newsletter: 377K Free, 18K Paid, $2M+ a Year — 450 Paid Subscribers in the First 6 Weeks After Going Paid
Lenny Rachitsky's newsletter earns $2M+/year from 377K free and 18K+ paid subscribers (a 4–5% conversion rate). Six weeks after going paid on April 7, 2020, it had 450 paid subscribers. The turning point wasn't the paywall itself — it was rebuilding the product as a Slack community.
22 Udemy Courses, 8 Bestsellers, $2,124 a Month on Average: Building a "Shelf of Courses" on a Global Platform
A Udemy instructor teaching coaching and video production published a revenue report covering 22 courses (8 of them bestsellers). Instructor income averages $2,124 a month (about ¥319,000), of which roughly ¥150,000 comes via Udemy itself. He discloses down to per-course profitability: unsold courses make ¥1,000 a month while bestsellers make tens of thousands of yen.
Damon Chen: Bought a GitHub Repo for $20K, Grew It to $1.5M ARR — the “Buy, Don’t Build” Indie Playbook
Former engineer Damon Chen grew Testimonial.to to over $2M cumulative revenue in four years, then in the early ChatGPT boom bought a pre-revenue repository (now PDF.ai) for $20K. Repositioned as "AI you can chat with about PDFs," it grew to $1.5M ARR within months. A defining example of indie development that buys the seed instead of building from scratch.
A high schooler's paid Discord bot nets ¥12,000/month profit — reading the logic behind pricing ¥500 on top of a ¥320 cost
Entering a Discord text-to-speech market full of free bots at ¥500/month, cost about ¥320 per 200,000 characters, and ¥12,000/month profit by year two. Even the signup pace is quantified.
8 failures, 3 hits in 5 years — the turning point where a solo developer with ¥0 revenue reached ¥200,000–¥1,000,000/month
Of 8 failed products earning ¥0 to a few thousand yen, one successful paid learning service hit ¥200,000–¥1,000,000/month within six months on 50–200 users. Laying out all 11 side by side reveals what actually split them.
The Revenue Record of 9 Udemy Courses — the First Took 100 Hours and Made $165, and What It Taught Produced a "¥1.5 Million Course"
Udemy bestselling instructor Naoto Takizawa published real data across 9 courses. His first course took about 100 hours and earned $165 (about ¥20,000) in a year, but a later course refined through iteration cleared $10,000 (¥1.5 million) in profit. Monthly students grew from 34 in the first month to 563 within a year. The explanation of the mechanics — including revenue shares (97% for self-referred sales / 37% for Udemy-sourced) — is invaluable.
SEO Blog Backlinko, 500K Monthly Visits, Sells to Semrush for Seven Figures: The Rare Strategy of Doing the Opposite of Mass Production
Brian Dean's SEO blog Backlinko drew 500,000 monthly visits with a strategy of publishing few articles but polishing each one to perfection, and was sold to SEO tool giant Semrush for seven figures (hundreds of millions of yen). A classic case in content strategy: winning at the polar opposite of "write a lot."
FAQ
- What is a solopreneur?
- Someone who runs a business without employees. Unlike freelancing, which sells time, a solopreneur typically owns an asset — a product, an audience, a site — that keeps earning without their direct labour.
- How far can one person scale?
- Documented ceilings here include $7M+/year from an open-source paid tier, $74K MRR from a social scheduling tool, and $12.5M lifetime from digital courses — alongside cases that plateaued at a few thousand yen a month.