Crab Fit alternative
Crab Fit is a clean open-source availability grid that already handles time zones. VennMeet differs after the grid: an "if needed" answer, ranked times that flag the worst local hour, and a confirmed meeting. Free, no accounts.
The short version. Crab Fit is a well-made, open-source, genuinely free tool, and it already lets each person view the grid in their own time zone. If you came looking for an alternative because of time zone maths, you may not need one. VennMeet differs in what happens after the heat map: a separate "if needed" answer, times ranked with the worst local hour flagged, and a confirmed meeting with a calendar file at the end. Stay with Crab Fit if you want the classic grid, GPLv3, and the option to self-host.
Why people look for a Crab Fit alternative
Crab Fit does what it says, so the reasons for looking elsewhere are specific rather than general complaints.
The heat map doesn't decide anything. Darker cells mean more people, and you hover to see who. That's the whole output. Turning it into "we're meeting Tuesday at 8" is still a human job, and in a spread-out group the darkest cell is frequently somebody's 6am without saying so.
Availability is one bit. You're free or you aren't. There's no way to record "I can make that but it's late for me", so people either mark it and get scheduled without complaint, or leave it off and silently shrink the group's options. Either way the thing that would have picked the fair time never gets asked.
The time zone is set at creation. Crab Fit asks the organiser to pick a time zone when the event is made, and participants can change their own view to see the grid in local hours. That works, but the display is per-viewer: you see your times, not everyone's. When you're trying to work out who is being asked to get up early, that's the fact you actually want.
Nothing is confirmed. There's no decision inside the event, so the result goes back to Slack or email, which is where the back-and-forth you were avoiding picks up again.
Where each one fits
Time zones. Both handle them, differently. Crab Fit converts to whatever zone you select, so each person can read the grid in their own hours. VennMeet gives each participant a row labelled with their city and their clock, so the organiser sees all of it at once rather than one view at a time. If your question is "what time is this for me", Crab Fit answers it. If your question is "what time is this for everyone, and who gets the worst of it", VennMeet is built for that.
Answering. Crab Fit hands you a blank grid and you drag across the times you're free, which is fast and needs no explanation. VennMeet asks the organiser to propose two or three windows first, and everyone answers inside those. More work for the person creating it, less for the ten people answering, because they pick between a few real options instead of describing their whole fortnight.
The "if needed" answer. Crab Fit has available or not. VennMeet adds a third state ranked below a clean yes. In a group with no common working hour this is the difference between a time nobody minds and a time that quietly costs one person their evening, and a binary grid can't tell those apart.
The result. Crab Fit shows overlap and lets you hover to see names. VennMeet ranks the candidates, putting times that work cleanly for everyone above times that need an "if needed", and marks the worst local hour on each. Then you confirm one and everyone gets an .ics file and a Google Calendar link.
Open source and self-hosting. Crab Fit wins here without argument. It is GPLv3 on GitHub with self-hosting guides in the wiki, and there are public instances run by universities and other groups. If you want to run your own scheduler, or you need the code auditable before your organisation will use it, that's a real and sufficient reason to stay. VennMeet isn't self-hostable.
Translations. Crab Fit maintains a community translation project, so it exists in a good number of languages. VennMeet is English only.
Side by side
| Crab Fit | VennMeet | |
|---|---|---|
| Price | Free, donation funded | Free, no paid tier |
| Account needed | No | No, for anyone |
| Time zones | Viewer picks their zone | One row per person, each in their own clock |
| Answering | Drag on a blank grid | Tap inside a few proposed windows |
| "If needed" answer | No | Yes, ranked below a clean yes |
| Ranked best times | Heat map, unranked | Yes, with the worst local time flagged |
| Confirmed time | No | Yes, with an .ics file and a Google Calendar link |
| Open source | Yes, GPLv3 | No |
| Self-hostable | Yes | No |
| Languages | Many, community translated | English |
Pricing
Both free. Crab Fit runs on donations and says so on the site, asking you to chip in so it can stay free for everyone, which is worth honouring if you use it regularly. VennMeet has no paid tier and no donation link. Neither of us gates the useful part behind a subscription, which distinguishes both from most of this category.
Who should choose Crab Fit
Choose Crab Fit if self-hosting or open source matters. That isn't a preference to argue with: if you need to run the thing yourself, audit it, or keep the data on your own infrastructure, VennMeet can't do any of that.
Choose it when availability is genuinely open. If the real answer is "show me the next two weeks and I will mark what I can", the blank grid captures more than proposed windows do.
Choose it if you need a language other than English, or if your group already knows it. The interaction is well judged and people pick it up without instructions.
Who should choose VennMeet
Choose VennMeet when the group has no good overlap. Across Sydney, London and San Francisco there's no hour that suits everyone, so the useful question is which compromise you're making and whether the person absorbing it agreed. The "if needed" answer and the flagged local hour are built for that; a heat map isn't.
Choose it when the decision has to land. If your actual problem is that the picture gets interpreted three ways and the thread restarts, a confirmed time with a calendar file is the point.
Choose it if people answer on their phones. VennMeet drops to a tap-to-answer list below 700px rather than asking for precise drags on a small grid.
Switching from Crab Fit
Nothing to migrate. Both are one link per event with no accounts, so switching is just using a different link next time. No export, no settings, no history.
The habit that changes is at the start: Crab Fit asks for a date range and a daily window and leaves the grid open, while VennMeet asks you to paint the windows that suit you before sharing. It takes an extra half minute and means the people answering choose between a few real options. Worth mentioning when you send the first link, since anyone used to the open grid will wonder where the rest of the week went.
FAQ
Is Crab Fit free?
Yes, and open source under GPLv3. It is funded by donations, with a link on the site asking for support so it can stay free.
Does Crab Fit handle time zones?
Yes. The organiser sets a time zone when creating the event, and participants can switch the display to their own so the times shown are local to them.
What does VennMeet do that Crab Fit doesn't?
A separate "if needed" answer instead of a single availability bit, a ranked result that flags whose local hour is worst, and a confirmed time at the end with a calendar file.
What does Crab Fit do that VennMeet doesn't?
It is open source and self-hostable, and it's translated into many languages. VennMeet is a hosted service in English only.
Can I self-host VennMeet like Crab Fit?
No. If self-hosting is a requirement, Crab Fit is the better choice and its wiki has guides for it.