Tandem vs Cal.com
Cal.com is open source, self-hostable and enormous in scope. It is a scheduling platform; Tandem is a sync tool that also schedules.
The short version
Cal.com wins on scope and on being open source. Tandem wins if what actually hurts is two calendars colliding, which Cal.com treats as a side feature.
| Feature | Tandem | Cal.com |
|---|---|---|
| Open source | No | Yes |
| Self-hosting | Docker image | Fully supported |
| Two-way calendar sync | Core feature | Limited |
| Privacy modes on mirrors | Three | n/a |
| Sync trace and drift repair | Yes | No |
| Teams and round-robin | No | Yes |
| App store | 4 integrations plus any URL | Large |
| Setup effort | Two clicks | Higher |
| Entry paid price | $12/month | $15/month |
Pick Cal.com if…
you want to self-host, you need teams and routing forms, or you want an app store. Cal.com is a bigger product and does not pretend otherwise.
Try it on two calendars
The free plan covers two connected accounts, forever. That is enough to see whether the sync does what you need.
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