cal.com vs Mastra
cal.com vs Mastra, compared side by side on 15 data points: what each one does, how big it is, what it has raised, the tech running each site, and what users report. We score both out of 100 on traction, team and visibility: cal.com is on 41/100 and Mastra on 77/100.
Where each one leads
cal.com
- domain rating: 92/100 against 76/100
Mastra
- our overall score: 77/100 against 41/100
At a glance
| Measure | cal.com | Mastra |
|---|---|---|
| What it is | Open-source scheduling infrastructure for individuals, businesses, and developers. | An open-source TypeScript/JavaScript framework for building AI agents, from the creators of Gatsby. |
| Category | Scheduling Software, Open Source, API Platform, Developer Tools | Agentic AI, AI Agents, Developer Tools, Open Source |
| Sells toBusiness model | B2B | B2B |
| Offering | Platform | Platform |
| Founded | 2020 | 2024 |
| Headquarters | Berlin, Germany | San Francisco, United States |
| Status | Active | Active |
Size, funding and growth
| Measure | cal.com | Mastra |
|---|---|---|
| Employees | Not published | 53 |
| Headcount growthLast 12 months | Not published | +204.5% |
| Total funding | Not published | $35.5M |
| Latest round | Not published | Series A |
| LinkedIn followers | Not published | 6,591 |
StartupHub scores
Our own 0-100 ratings. They measure company strength and site quality, not which product suits you.
| Measure | cal.com | Mastra |
|---|---|---|
| StartupHub scoreOur 0-100 rating | 41/100 | 77/100 |
| Traction | Not published | 70/100 |
| Team | Not published | 90/100 |
| Community | Not published | 38/100 |
| Search visibility | 10/100 | 68/100 |
| Quality | 68/100 | 78/100 |
| Agent readinessHow well an AI agent can read and act on the site | C (61/100) | D (58/100) |
| Domain ratingLink authority, 0-100 | 92/100 | 76/100 |
Technology
Detected on each public site, so it reflects the marketing stack as well as the product.
| Measure | cal.com | Mastra |
|---|---|---|
| Hosting | Not detected | Vercel |
| CDN | Cloudflare | Vercel |
| CMS | Framer | Not detected |
| Frameworks | Not detected | Next.js, Tailwind CSS |
| Open source | Yes | Yes, 15,100 GitHub stars |
| Self-hostable | Yes | Yes |
Product and pricing
| Measure | cal.com | Mastra |
|---|---|---|
| Key features | Not published | AI Agent Framework, Workflows, RAG, Evals, Memory & Tool Selection, Open Source & Modular |
| Current offer | 20% off for 12 months | Not published |
What users say
| Measure | cal.com | Mastra |
|---|---|---|
| Community ratingVisitor votes on StartupHub | Not published | 5.0/5 from 2 votes |
cal.com vs Mastra: common questions
Which is better, cal.com or Mastra?
On our 0-100 score Mastra rates higher (77/100 against 41/100). The score weights traction, team, visibility and profile completeness, so it reflects company strength rather than which product suits you. We compare the two on 15 data points above: read the rows that match what you are buying for.
How do cal.com and Mastra compare on the numbers?
cal.com leads on domain rating (92/100 against 76/100). Mastra leads on our overall score (77/100 against 41/100).
Read the full cal.com review and pricing or the Mastra review and pricing. You can also browse other cal.com alternatives we track.