OpenCPA

An open-source CPA exam study platform that you can study with Claude.

OpenCPA is a free, community-maintained alternative to commercial CPA review courses. It pairs an adaptive question engine and realistic task-based simulations with Claude as a study partner, connected through your own Claude account.

Live: opencpa.pages.dev

Status: alpha. The platform is deployed end to end (site, API, database, CI). The question bank grows in reviewed batches, FAR first: today there are 318 FAR questions (with 771 new-number versions, 1,089 problems in all), 21 FAR simulations and 25 BAR questions. Every task in the 2026 FAR blueprint has at least two reviewed questions, and FAR simulations are under way toward 50 across all three blueprint areas. The FAR goal is 1,600 distinct questions, the size of Becker's FAR bank; AUD, REG, ISC and TCP come after FAR is complete, with a long-term goal of about 2,000 questions per section.

---

Features

Live now

• Practice sessions. Pick a section and a length (a slider, 5 to 100 questions); the server builds a session, with questions and simulations on separate tabs as on the exam, that mixes blueprint areas by weight, brings back questions when they're due for review and leans toward your weak topics. Move back and forth between questions with Previous and Next; a pick you haven't submitted is kept. Your first session in a section is a short diagnostic, and leaving the page never loses your place.
• Question versions. Numeric questions come in several versions with different numbers, so a repeat is a new problem, not a memorized answer.
• Library. Browse every exam by blueprint area and topic, practice any single topic, and look up any question in the archive (unanswered, missed, correct). Search understands accounting synonyms and ASC numbers, so “fixed assets” finds PP&E and “DTL” finds income taxes. Answers stay hidden until you've attempted a question.
• Progress. Coverage by section ("seen 12 of 318"), mastery by blueprint area, and mastery by topic, weakest first.
• Simulations. Task-based simulations with exhibits, journal-entry grids, numeric, research and dropdown (select) tasks, graded deterministically with partial credit.
• Blueprint-aligned content. Every question and simulation is tagged to the AICPA blueprint by section, content area, topic and skill level, and every item passes an independent review before it's served.
• Adaptive review. Spaced repetition (FSRS) schedules individual questions, and results roll up into a mastery map by blueprint area.
• Study with Claude. Add OpenCPA as a connector in your own Claude account, and Claude can look up the question you just answered and explain it, using the official rationale. It explains; it never grades, and it won't reveal anything from a mock exam you haven't finished.
• Mock exams. A full-length, timed FAR exam in the real format: 5 testlets (25 and 25 questions, then 2, 3 and 2 simulations), a 4-hour clock kept by the server, the optional 15-minute break, flags, strike-outs and locked testlets, plus a pause button for studying at home. Nothing is graded until the end; the report scores multiple choice and simulations 50/50 (no invented 0–99 scaled score), breaks results down by area, topic and skill, shows time per testlet and any pauses, and lets you review every item with its answer. Past exams are listed on the Progress page. Start one from Practice.
• Accounts. Sign in with GitHub to keep your progress on every device; whatever you did before signing in moves into your account. Signing in is optional, and you can delete your account (or a device's data) at any time.

Planned

• More FAR simulations, to 50 across all three blueprint areas (21 so far), then simulations for the other sections.
• A literature panel for simulations, with research tasks.
• Email sign-in (a one-time link, no password), once the site has its own domain.
• Advanced settings for weighting practice toward your strengths or weaknesses.

Architecture

Layer	Tech
Frontend	React + Vite on Cloudflare Pages
API	Hono on Cloudflare Workers
Database	Cloudflare D1 (SQLite)
Claude	Remote MCP connector on the API; students use their own Claude account
Storage	Cloudflare R2 (planned: exhibits, media)
Auth	GitHub OAuth; anonymous device id when signed out; email link planned

opencpa/
├── apps/
│   ├── web/          # React + Vite frontend
│   └── api/          # Hono Worker API, D1 migrations
├── packages/
│   ├── engine/       # Grading, FSRS scheduling, mastery, session and mock exam selection, exam clock
│   └── schema/       # Content schema (zod), shared types
├── content/          # One YAML file per question/simulation
│   ├── far/  aud/  reg/
│   └── bar/  isc/  tcp/
└── scripts/          # Content validation + bundling

Roadmap

• Monorepo scaffold: React site, Hono API, D1 database, content schema, CI
• Deployed to Cloudflare (Pages + Workers + D1) with automatic deploys from main
• First reviewed FAR batch (~25 questions)
• Practice sessions with adaptive selection and a diagnostic
• Claude connector: study with your own Claude account
• Question versions (new numbers on every numeric FAR question)
• Task-based simulations (journal-entry grid, numeric, research, select)
• Library: browse by exam and topic, topic practice, question archive
• Library search: finds related topics and questions, not just exact wording (synonyms, ASC numbers, typos)
• Mock exams: timed FAR exam in the real testlet format, with a score report
• Two or more reviewed questions for every FAR blueprint task (318 questions)
• Finish FAR: 1,600 reviewed questions (318 done), 50 simulations across all three areas (21 done), skill mix inside the blueprint ranges
• Remaining sections, in reviewed batches (BAR, then AUD and REG, then ISC and TCP)
• Advanced practice settings
• Accounts: GitHub sign-in, progress syncs across devices, account deletion
• Email sign-in (needs a custom domain)
• Practice tabs: questions and simulations on separate tabs in a session, as on the exam
• Rate limiting, UI redesign, custom domain
• Literature panel and research tasks

Content

All content lives in content/ as plain files, so contributions are just pull requests. CI validates each item against the schema.

id: far-leases-0001
type: mcq
blueprint:
  section: FAR
  area: Area II — Select Balance Sheet Accounts
  topic: Leases
  skill: Application
review:
  status: draft # only "reviewed" items are served
  references: [ASC 842-20-30-1]
stem: >
  A lessee signs a 5-year lease ...
choices:
  - { id: A, text: '$84,248', rationale: 'Correct: $20,000 × 4.2124.' }
  - ...
answer: A
explanation: >
  ...

Original content only. Do not submit AICPA-released questions or material from commercial review providers (Becker, UWorld, Gleim, etc.). They are copyrighted.

Getting started

git clone https://github.com/HaydenHarms/opencpa.git
cd opencpa
pnpm install
pnpm db:migrate:local   # create the local D1 database
pnpm dev                # web on :5173, API on :8787

Requires Node 22+ and pnpm 10+. pnpm test runs the engine and schema tests; pnpm content:validate checks every content file. To try sign-in locally, see docs/accounts.md.

Deployment

Pushes to main deploy automatically:

• Site: Cloudflare Pages builds apps/web (build command pnpm --filter @opencpa/web build, output apps/web/dist). Set VITE_API_URL to the API's address and NODE_VERSION=22.
• API: GitHub Actions runs the checks, applies any new D1 migrations, and deploys the Worker. Needs the repo secrets CLOUDFLARE_API_TOKEN (Workers Scripts Edit + D1 Edit) and CLOUDFLARE_ACCOUNT_ID.
• Allowed origins: the API only accepts browser requests from the origins in ALLOWED_ORIGINS (apps/api/wrangler.toml). Add any new domain there.

Forking to run your own instance? Create your own D1 database, put its id in apps/api/wrangler.toml, and follow the same steps.

Contributing

Contributions are welcome, especially new questions, simulations, and explanations reviewed by CPAs or CPA candidates. See CONTRIBUTING.md for the content format and review checklist.

Disclaimer

OpenCPA is not affiliated with the AICPA, NASBA, or any state board of accountancy. "CPA" is used descriptively. Content is for study purposes only. See the site's Terms of Use and Privacy Policy.

License

Code: MPL-2.0. Content: CC BY-SA 4.0.