If you are talking in Ruby check that out:
def created_at_pretty
_now = Time.now
dif = (_now - self.created_at).to_i
if dif < 60
dif = "#{dif} seconds"
elsif dif > 59 && dif < 120
dif = "1 minute"
elsif dif > 119 && dif < 3600
dif = "#{dif/60} minutes"
elsif dif > 3599 && dif < 7200
dif = "1 hour"
elsif dif > 7199 && dif < 86400
dif = "#{dif/60/60} hours"
elsif dif > 86399 && dif < 172800
dif = "1 day"
elsif dif > 172799 && dif < 5184000
dif = "#{dif/60/60/24} days"
elsif dif > 5183999 && dif < 10368000
dif = "1 month"
elsif dif > 10367999 && dif < 62208000
dif = "#{dif/60/60/24/30/12} months"
elsif dif > 62207999 && dif < 124416000
dif = "1 year"
elsif dif > 124415999
dif = "#{dif/60/60/24/30/12/12} years"
end
"#{dif} ago"
end