AI Side Hustles
AI Coding AgentNamed in 4 case studies

OpenAI Codex

OpenAI's coding agent, used through a ChatGPT plan or an API key. Documented founders say they used it to vibe code a paid budget app in a weekend, to build card scanner apps and an AI video clipping app, and to run a one-person marketing agency. In our data, 4 sourced cases name OpenAI Codex as a tool they used. Of those, 4 report a monthly figure, ranging from $11,200 to $120,000 a month (median $20,000). These figures are as reported by each source: 0 independently documented, 0 source-supported and 4 self-reported. They are examples, not typical results.

The word Codex in white on a soft blue and purple gradient.
Image: OpenAI (official site). View source (opens in a new tab)
Visit Official SiteOfficial Pricing PageNo affiliate relationship. This is a plain link.
Pricing

Comes with ChatGPT plans. The official page listed Free at $0, Go at $8/month, Plus at $20/month and Pro at $100/month for individuals, and Business at $20. It can also be used with an API key at API rates.

Free plan: Yes. The Free plan includes Codex for quick coding tasks, with limits.

Checked on the official pricing page on October 27, 2026. Prices change and can vary by region, tax, and billing period.

How It Is Used in Our Cases
  • Vibe coding a first version of an app from a template
  • Shipping feature requests quickly
  • Running coding tasks alongside ChatGPT
Limitations
  • Usage is shared with ChatGPT and capped by plan
  • Model availability changes often
  • Generated code still needs review and testing
In the Case Studies

Case Studies Using OpenAI Codex

4 case studies
Social preview image from vugolaai.com, the official site.
Image: vugolaai.com
October 11, 2026
1 source

A 19-year-old with no coding experience built an AI video clipping app to about $11K MRR in five months

Vugola (Vadim, @VadimStrizheus on X)

Vadim, 19, worked at a marketing startup from age 17 and quit to build software with no coding experience. He noticed how many podcast, gaming and stream clips filled his feeds and decided to build a clipping tool for a proven market. He spent about four months building Vugola, began marketing it in March 2026 and says it now makes about $11,200 in monthly recurring revenue with roughly 400 paying users.

Read original source
Reported figure
About $11K MRR(recurring revenue)
Evidence levelSelf-Reported
Tools:
Inspect Case
Social preview image from scanemon.com, the official site.
Image: scanemon.com
June 8, 2026
1 source

A self-taught developer turned his card collecting hobby into two scanner apps that he says make $120K a month

Cardstock and Scanemon (Kyle Fowler)

Kyle Fowler launched Cardstock six years before the interview. It began with three people in a basement making a few hundred dollars a month. Cardstock lets collectors scan a sports card with their phone camera, find its value and track their collection. A year before the interview, his team launched Scanemon, the same idea for Pokemon cards.

Read original source
Reported figure
$120K a month(revenue)
Evidence levelSelf-Reported
Tools:
Inspect Case
Screenshot of the ravenopus.com homepage.
Image: ravenopus.com
August 17, 2026
2 sources

A laid-off eBay analyst runs a one-person marketing agency on AI agents, with retainers of $20,000 to $30,000

Linara Bozieva (Ravenopus)

Linara Bozieva spent 11 years at eBay before being laid off, then founded Ravenopus in San Jose in May 2024. She is the only human, running about 30 to 35 specialized AI agents for strategy, research, creative, media and conversion work. Forbes reports retainers in the $20,000 to $30,000 range and that the bootstrapped company has been profitable since its first day, she says.

Read original source
Reported figure
Retainers of $20,000 to $30,000 a month(revenue)
Evidence levelSelf-Reported
Tools:
Inspect Case
Tarsi app icon, a white cartoon tarsier with big round eyes peeking up on a green rounded square.
Image: Tarsi (official App Store listing)
May 23, 2026
1 source

A developer vibe coded a paid budget app in a weekend with Codex and says it made about $20K in its first month

Tarsi (Bryl Lim)

Bryl Lim, from the Philippines, built Tarsi as a live demo for a university talk about vibe coding and published it because he already had a developer account. People started buying it. Tarsi is an offline-first budget tracker with a tarsier mascot, sold as a one-time purchase. He told the Tap & Swipe podcast it made roughly $20K in its first month across iOS and Android and topped the paid charts in several countries, and he has repeated the approach with a trip planner and a workout tracker.

Read original source
Reported figure
About $20K in its first month(revenue)
Evidence levelSelf-Reported
Tools:
Inspect Case
Alternatives

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ChatGPT

AI Assistant

OpenAI's general-purpose AI assistant. In our documented cases it is used to draft reports, brainstorm product slogans, write first drafts of client posts, and generate code for digital products.

Free plan: Yes. Free plan with limits on uploads, image creation, and deep research.

Pricing: Free plan, plus paid Go, Plus, and Pro plans for individuals and Business and Enterprise plans for teams. Exact prices were not shown in the version of the page we could read; check the official page for your region.

Checked October 17, 2026

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AI Model API

OpenAI's developer platform for building GPT models into your own apps. Documented founders use it inside voice-note apps, resume and cover letter tools, writing assistants and support agents. This is separate from a ChatGPT subscription.

Free plan: No free plan listed; usage is billed per token.

Pricing: Pay as you go, priced per 1 million tokens and varying by model. For example, the official page listed gpt-6-luna at $0.10 per 1M input tokens and $0.50 per 1M output tokens (standard), and gpt-6-astra at $10.00 input and $50.00 output.

Checked October 20, 2026

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Dark Claude Code Docs preview card reading Getting started, Overview, and a line describing Claude Code as an agentic coding tool.Official image

Claude Code

AI Coding Agent

Anthropic's agentic coding tool. It reads a codebase, edits files and runs commands from the terminal or an IDE. Documented founders say they used it to build mobile apps, a data API and a store builder, and to run daily content and client routines. This is separate from chatting with Claude itself.

Free plan: No. The official comparison lists Claude Code on Pro and Max, not on Free.

Pricing: Included in the paid Claude plans, not the Free plan. Pro is $20/month billed monthly or $17/month with annual billing; Max starts at $100/month with higher usage.

Checked October 27, 2026

Used in 12 documented casesView Profile
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