Lua Base64 Benchmark - https://github.com/kostya/benchmarks/tree/master/base64

base64_test.lua

-- base64 lib code: https://github.com/ErnieE5/ee5_base64
base64 = require("base64lib")

local str_size = 1000000
local tries = 100

local plain_string, encoded_string = '', ''

local function print_results(size, from_time)
  print(string.format('%s, %s', size, (os.clock() - from_time)))
end

-- trying to use '..' operator inside a loop is a huge stupid choice
-- http://stackoverflow.com/a/19139394/1057087
local buf = {}
for i=0,str_size do buf[#buf+1] = 'a' end
plain_string = table.concat(buf)

print("encode: ")

local s,t = 0, os.clock()
for i=0,tries,1 do
  encoded_string = base64.encode(plain_string)
  s = s + string.len(encoded_string)
end

print_results(s, t)

print("decode: ")

local s,t = 0, os.clock()
for i=0,tries,1
do
   local str3 = base64.decode(encoded_string)
   s = s + string.len(str3)
end

print_results(s, t)