Day trip to Venice from florence

Yes, doable if rushed.
You can look up train times and buy tickets (cheaper if bought in advance) on the Trenitalia website: http://www.trenitalia.com/tcom-en
Be sure to use the correct names of the stations, and not English translations: "Firenze S. M. Novella" and "Venezia S. Lucia".
It takes 2h05 and if you book ~2 months in advance, prices are ~€22-26 each way. For example:

From: Firenze S. M. Novella (07:15) To: Venezia S. Lucia (09:20)
Date: 07.01.2019 FRECCIAROSSA 1000 9400 seats info 1 Adult Super Economy - Standard
From: Venezia S. Lucia (19:25) To: Firenze S. M. Novella (21:30)
Date: 07.01.2019 FRECCIAROSSA 1000 9457 seats info 1 Adult Super Economy - Standard
Final price (VAT included) : 49.80 €

Thanks so much

Don't try to see Venice on a day trip from Florence. You won't have enough time to see that much. Plan on at least one night in Venice. B&Bs near the main train station are not expensive.

Hi,

I agree that you should spend at least one night in Venice to fully appreciate the charm, which is more pronounced in the evening.

But if one day trip is all you have time for, then do it by all means - and then hope/plan to come back for a longer stay.

I really don't recommend this. You need more time in Venice so you can wander around the non-touristy areas. If you just travel there for the day from Florence you're going to be surrounded by mobs of other visitors everywhere you're likely to go, and I think there's a very high probability you won't much like the city. Why spend the money for an inferior experience? It's not as if Italy doesn't have tons of other wonderful places more suitable for a day-trip.

I wouldn't do it, either. Venice needs more time. If you must take a day trip, try Siena or Lucca/Pisa.

It's 149 miles from Florence to Venice, so it's perfectly do-able. And I have made it as a day trip. Unfortunately, I missed that radar camera on the causeway from the mainland while running 1.8 mph over the speed limit. It cost me dearly a year later when a ticket was received. And daily parking in the garages is not cheap in Venice..
Just take the train up there.

It’s doable and I’ve done it many times, including before high speed trains, when the trip took 3 hours.

Obviously if you could spare a night or two (or three) in Venice, it would be much better, but I’m not going to discourage you from going on a day trip if you don’t have more time. Venice is too beautiful and unique to pass up.

And don’t be deterred by those who tell you you will go in the next trip. Cemeteries are full of people who thought they’d visit the same country a second time.

It will cost about 200 EUR for the 4 of you and you have to book nonrefundable well in advance, maybe 3 months or more to get that price. Depends on the time of year.

A bit more flexible is the Same Day Round Trip ticket (A/r in Giornata) which can be bought up to midnight the night before. That will cost 276 EUR for the 4 of you. But tickets can be limited, so maybe don't wait until the last minute.

When you get there, buy 4 24-hour vaporetto passes for 20 EUR each.

We did Florence to Venice and back in a day this past May, using the trains that the first poster mentioned. Plenty of time to get an impression of the city and take a lot of pictures and eat a nice lunch. Probably too rushed if you want to go inside a lot of places, you might have to pick one or two to go inside and make the rest of the day a walking trip. We did our own walk, no guide, but I had been there once previously so had an idea how to make use of the limited time. My guess is two teens would like the trip, even if it seems rushed for those of us who are older. We bought our tickets one day before, at the Florence train station, 34.50 euros per person each way ( I still have the tickets and am holding them in front of me now :)

Yep. 34.50 times 8 (4 round trip tickets) is 276 EUR.