Can I use this for client bookings?

Not well. There is no concept of your own availability here - you propose dates and people mark them. For one-to-one bookings from a live calendar, a booking page is the right tool.

Does it need access to my calendar?

No. Nothing is connected and nothing is read. Once a date is decided, you get a calendar file to add, which is the only place a calendar is involved.

Yes, with no paid tier and no feature held back.

A Calendly alternative for group dates

Calendly and Who can when? solve different halves of scheduling. Calendly publishes one person's free slots so somebody else can book one. Who can when? proposes a few dates to a whole group and counts who can make each. If the problem is twelve people and one evening rather than one person and one diary, the poll is the right shape - and it is free, with no account and no calendar to connect.

Which one you actually need

Ask who is doing the choosing. If one person is picking from another person's availability - a client booking you, a candidate booking an interview slot - a booking page is right, and this is not it.

If everybody has to agree, a booking page cannot help: it has no way to know that the slot suiting person one is impossible for persons three, four and seven. That is a counting problem, and it wants a poll.

What you get here

No connected calendar, on either side. Nothing reads your diary and nothing needs permission to.
No account, for you or for anyone you invite.
Yes, maybe and no against each proposed date, with a live count under every one.
Answer from the email, so an invitee never has to open a page at all.
A calendar invitation once you pick, which is where the two tools finally do the same thing.

Why nothing connects to your calendar

Because it would buy very little and cost a lot. Reading your calendar tells you nothing about the eleven other people, who are the actual constraint, and it turns a page anyone can answer into one that needs an account, a permission grant and a policy about what we do with what we saw.

The date poll asks the question instead. It is slower by about thirty seconds and it works for everyone.

Common questions

Can I use this for client bookings?: Not well. There is no concept of your own availability here - you propose dates and people mark them. For one-to-one bookings from a live calendar, a booking page is the right tool.
Does it need access to my calendar?: No. Nothing is connected and nothing is read. Once a date is decided, you get a calendar file to add, which is the only place a calendar is involved.
Is it free?: Yes, with no paid tier and no feature held back.

Ready when you are

Coming from something else

How this compares with the other tools people use for the same job.

Group scheduling poll Create a scheduling poll for a group in about a minute. Propose dates, share one link, and see at a glance which date the most people can make.
Board meeting scheduling Non-executives, investors and a founder, none of whom share a calendar system. Propose the dates, collect the answers in one grid, and stop chasing.
Client meeting scheduling Free/busy stops at your company boundary. Propose dates the client can answer in three taps, without an account or a calendar connection.