Here’s my official answer as a professional comedy writer, maid of honor speech expert and wedding guest:
Aim for about 5 minutes.
Why do I say “about 5 minutes?”
Because if it’s a little more or less than 5 minutes, you’re still in the right ballpark.
If you don’t have a lot to say, or you don’t know the person well and you keep it short and sweet at 3 minutes, that’s totally fine.
If your speech creeps up to 7-ish minutes, that’s ok too.
The most important thing isn’t the size of your speech, it’s the structure – and by that I mean, does it have one?
Of course your maid of honor speech is going to be heartfelt and funny. You love this girl. You’ve got a ton of stories. But your listeners have to be able to follow those stories.
A great maid of honor speech has a clear beginning, middle and end.
There’s nothing worse than listening to a speech that gets off to a great start and then watching it sink like a stone.
Your maid of honor speech should be a snowball rolling downhill, gathering momentum, telling us everything we need to know in a clear, easy to follow way, building to a strong natural finish — your toast.