Outlook vs Thunderbird
Outlook vs Thunderbird, compared side by side on 9 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: Outlook is on 8/100 and Thunderbird on Not scored yet.
Where each one leads
Outlook
- agent readiness: 29/100 against 25/100
Thunderbird
Leads on none of the measures we hold for both companies.
At a glance
| Measure | Outlook | Thunderbird |
|---|---|---|
| What it is | Microsoft's integrated suite for email, calendar, contacts, and task management. | Free and open-source email client for managing email, calendars, and contacts. |
| Category | Email, Productivity Software, Personal Information Manager, Collaboration Tools | Email Client, Open Source, Productivity Software, Personal Information Manager |
| Sells toBusiness model | B2B | B2C |
| Offering | Software | Software |
| Founded | Not published | 2003 |
| Headquarters | Redmond, United States | Not published |
| Status | Active | Active |
Size, funding and growth
| Measure | Outlook | Thunderbird |
|---|---|---|
| Employees | Not published | 48 |
| Headcount growthLast 12 months | Not published | +97.2% |
| LinkedIn followers | Not published | 3,428 |
StartupHub scores
Our own 0-100 ratings. They measure company strength and site quality, not which product suits you.
| Measure | Outlook | Thunderbird |
|---|---|---|
| StartupHub scoreOur 0-100 rating | 8/100 | Not published |
| Search visibility | 8/100 | Not published |
| Agent readinessHow well an AI agent can read and act on the site | F (29/100) | F (25/100) |
| Domain ratingLink authority, 0-100 | 93/100 | 88/100 |
Technology
Detected on each public site, so it reflects the marketing stack as well as the product.
| Measure | Outlook | Thunderbird |
|---|---|---|
| Hosting | Azure | Not detected |
| CDN | Not detected | Cloudflare |
| Open source | No | Yes |
| Self-hostable | No | Yes |
What users say
| Measure | Outlook | Thunderbird |
|---|---|---|
| Reddit sentimentThreads we track | Not published | 1 positive, 3 negative across 6 threads |
“Tuta Mail & Tuta Calendar are now available as add-ons in Thunderbird. Find out how to add Tuta as an add-on 👉 https://tuta.com/blog/tuta-add-on-in-thunderbird Enjoy! ❤️”r/tutanota
Outlook vs Thunderbird: common questions
Which is better, Outlook or Thunderbird?
On our 0-100 score Outlook rates higher (8/100 against Not scored yet). 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 9 data points above: read the rows that match what you are buying for.
How do Outlook and Thunderbird compare on the numbers?
Outlook leads on agent readiness (29/100 against 25/100).
What do real users say about Outlook and Thunderbird?
Thunderbird: 1 positive and 3 negative mentions across 6 Reddit threads we track, mostly in r/tutanota.
Read the full Outlook review and pricing or the Thunderbird review and pricing. You can also browse other Outlook alternatives we track.