Today, I have a blog entry for you about a common misunderstanding: the difference between “too” and “either”. Basically, it’s very simple: we use both “too” and “either” to say that something is also true for a second person or thing. The difference is that we use “too” for positive statements and we use “either” and “neither” for negative statements. For example:
I like pizza, and my wife does too.
I don’t like carrots, and my husband doesn’t either.
A: I’ve been to Korea many times.
B: Oh really? I have too. What’s your favorite place in Korea?
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A: I’ve never been to South America.
B: I haven’t either, but I’d really like to go there one day.
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A: I can play the piano.
B: Oh really? Me too!
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A: I can’t cook very well.
B: Me neither.
There is no difference in meaning between “either” and “neither”. We use “either” when there is another negative word in the sentence such as “not” or “never”. For example:
A: I’ve never tried scuba diving.
B: Oh yeah? I haven’t either.
However, we use “neither” when there is no other negative word in the sentence. For example:
A: I’ve never tried scuba diving.
B: Oh yeah? Neither have I.
So, we can say “Neither have I.” or “I haven’t either.” but we CANNOT say: “I haven’t neither.” because there are two negative words in the sentence.
English Help Online's Blog 
ShadowTwin Said:
on July 25, 2010 at 12:04 am
hey there,
wanna say thanks for this blog, i finally know the difference..it really helps me =D .. btw, love the design, very wonderful.
damian Said:
on June 6, 2012 at 10:02 am
Awesome. Thank you for the help on this. I had it figured out in my head, but wasn’t sure and couldn’t verbalize it as well as you did. Thanks!
Kwangmireu Said:
on July 4, 2012 at 3:01 pm
Oh yeah, i got it now!
Thank u..
Ladan Said:
on June 28, 2013 at 4:10 pm
bonjour
really thank you forfluent and simple explanation.
really thank you!
MARIA CÉLIA VALLE PEREIRA Said:
on August 13, 2013 at 9:11 am
thank you for your help
Found In Folsom Said:
on February 22, 2014 at 4:21 am
Thank you for this post. I accidentally said me either in place of me too and then went into a discussion with friends….as to which usage is right. I searched online and landed here.