Design and diagrams decision
Gamma
Build if you only need prompt→slide generation and export; reproducing Gamma's full product (hosting, analytics, collaboration, advanced multimodal models, and SOC2 compliance) is substantially more work and operationally heavy.
Visit website↗$12/mo
$144/yr
Not verified against a pricing page.
$50one-off30 h to build
$50/mo8 h/mo upkeep
On cash alone, building overtakes the subscription at 5 seats.
Open-source builds that already do this
Every project below is open source and already does this job today. Fork one, self-host it, or take the parts you need - the build prompt further down assumes an empty file, and this is the shortcut past that. Licences differ; check the one on each card before you ship. All Gamma alternatives, with the arithmetic →
What a replacement has to do
- Turn a user prompt or uploaded file into a styled slide deck and export as PPTX/PDF.
What it still won’t have
- Hosted website publishing and multi-domain hosting
- Advanced analytics and detailed engagement metrics
- Collaboration / real-time multi-user editing
- Access to the most advanced multimodal models (text, image, video)
- SOC 2 compliance and associated security guarantees
What remains hard
- Compliance and regulation
We're a SOC 2 Type II compliant organization.
First-year cost
Keep paying
Paying is—cheaper in year one.
On cash alone, building overtakes the subscription at 5 seats.
Money you would actually spend
Time you would spend
—
What you would spend
What we assumed
The verdict above measures whether you could build it. This one is only about money.
Runnable build prompt
Build a minimal AI presentation generator using Node.js (Express) + React for the frontend, Postgres for storage, and OpenAI (or compatible) for text/image generation. In scope: accept a text prompt or upload PDF/PPTX, extract/normalize content, call the model to produce slide titles and bullet content, map content to a small set of responsive slide templates, render previews in-browser, and export/download PPTX and PDF using python-pptx via a simple microservice. Out of scope: real-time multi-user collaboration, hosted website publishing, advanced analytics, SOC2 compliance. Include error handling for API/model failures, rate limits, input validation, and an automated test suite for API endpoints and export correctness.
How we checked
How the score was reached
- Partly verdict base52
- An open-source build was found+5
- 5 cited sources+3
- 3/3 assessment runs agreed+4
- Hard moats found in the evidence-3
- Evidence score61
The base comes from the verdict. Everything under it is a check that either happened or did not, and each one is a fact frozen in this record rather than a judgement made at render time - so the same evidence always produces the same number.
How scoring works →Cited sources · 5
Every page the run actually retrieved.
- official productGamma | Best AI Presentation Maker & Website Builder
- official pricingPlans and pricing | Gamma
- official pricingPlans and pricing | Gamma (compliance note)
- open sourceONLYOFFICE/DocumentBuilder
- open sourceattakei/sphinx-revealjs
Integrity checks
What held up, and what did not.