WhittleOS vs SpinBuild

A side-by-side comparison built from both listings. Blank cells mean the company has not given that detail; we never guess.

WhittleOS compared with SpinBuild
Detail	WhittleOS	SpinBuild
What it does	A startup decision engine for solo founders that kills weak ideas before they waste your months	AI platform for building websites and web apps from plain-language descriptions
Stage	Not given	Not given
Founded	Not given	Not given
Based in	Not given	Not given
Pricing model	Paid	Freemium
Pricing	Starter: $19 (2 credits); Founder Discovery Pass: $49 (6 credits); Multi-Market: $99 (15 credits); Working Founder: $149 (30 credits). Credits never expire. New accounts receive 2 free credits for any run except Discovery.	Starter plan is free forever with no credit card required. New accounts get 250 welcome credits for the first month. Paid plans available with monthly credits that reset on the first of each month and do not roll over. Cost depends on the AI model chosen, thinking level, and work required per reques
Key features	12 deal-breaker checks for evaluating ideas Market discovery with live searches across real sources Whittle Score ranked 0–100 from fixed rubric computed in code Build it / Test it first / Drop it verdict with reasons Evidence linked to source pages or marked not verified Up to 5 ranked idea candidates per Discovery run Deep-dive modules: Kill My Idea, Pricing Power, Support Burden, Platform Risk, Pivot Wedge Prepaid credits with no expiration Free founder profile read and 2 free credits on signup Async-only validation with no customer calls required	Support for 11 stacks: Next.js, React, Vue, Svelte, Astro, Preact, Vite, Express, Fastify, Koa, HTML/CSS/JS Choice of AI models in one dropdown including Claude Opus, Claude Sonnet, GPT and hundreds of others Live preview that updates as code is written Code review with per-file approval and diffs One-way sync to GitHub repository you own Private Postgres database per project One-click HTTPS deployment MCP support for Cursor, Codex, Claude Code, Grok Build Kernel-isolated containers for app security Version history with rollback to any previous state
What makes it different	No subscription or sales calls—pay per decision with credits that never expire	Vibe coding: describe what you want instead of writing every line yourself Real full-stack apps with live preview, not just mockups or templates Your code in a GitHub repo you own, yours to keep and run elsewhere Switch AI models in one dropdown to balance speed, capability and cost
Community votes	0	0
DR (Domain Rating by Ahrefs)	4 +1 (up) since last check	Not checked yet no change since last check
Trust Flow (Majestic)	18	1
Citation Flow (Majestic)	24	20
Referring domains (Majestic)	51	3

5 details filled in for both companies.

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