"By accident" or "on accident"

[don't let's]

After thinking about for a while they both sound natural to me.

[Daddy]

After thinking about for a while they both sound natural to me.

on purpose
by accident

[ME##]

I split me milk by accident.



Usually I try to use 'by', but sometimes 'on' slips out of me.

[don't let's]

on purpose
by accident

I don't even know anymore 

[Lotos]

I did it by accident.
I spilled the soda on accident.

That's how I use that word.

[Kalahari Inkantation]

I usually say "on". :'(

[[REDACTED]]

How do people mix up "on purpose" and "by accident?"

[Samus Aran]

I think both of them sound retarded, honestly, and I try to avoid them.

[Nyerp]

Yeah, I tend to lean towards "accidentally".

[Thyme]

Yeah, I tend to lean towards "accidentally".

Come to think of it, so do I. Sometimes I just don't say anything, as if it had to be taken for granted that it was done accidentally:

I spilled the milk.

[Nyerp]

Come to think of it, so do I. Sometimes I just don't say anything, as if it had to be taken for granted that it was done accidentally:

I spilled the milk.

what if they think you did it on purpose...er, purposely

[[REDACTED]]

Yeah, I tend to lean towards "accidentally".

[YPrrrr]

what if they think you did it on purpose...er, purposely

purposefully

[Nyerp]

purposefully

nice try...?

[YPrrrr]

nice try...?

? I'm just saying that's the adverb form of purpose