When one transforms an output containing machineprecison-numbers to a input, many trailing 0s appears. For example : Evaluate the following expression : {{41.`,19.200000000000003`}, {41.`,39.5`}, {33.6`,49.300000000000004`}, {33.2`,59.800000000000004`}, {33.2`,61.800000000000004`}} > {{41., 19.2}, {41., 39.5}, {33.6, 49.3}, {33.2, 59.8}, {33.2, 61.8}} Then copy-paste this output. The result is a input cell with all the trailing 0s. I need to Round the output values so that the input form is short (It is not a problem of number formatting/rendering since the numerical values are changed). **Test already done, without success :** First, a preamble that shows that this possible niceValue=49.3 niceValue //InputForm > 49.3 > 49.3 Then, a example of a difficult case : irritatingValue=49.300000000000004` irritatingValue //InputForm > 49.3 > 49.300000000000004 Unsuccessfull attempts : This seems to work : Round[irritatingValue,1. 10^-6] //InputForm > 49.3 But this does not : Round[irritatingValue,1. 10^-5] //InputForm > 49.300000000000004 so the "solution" `Round[..., 1. 10^-n]` is inacceptable. Because the problem is certainly due to the binary representation of numbers represented in base 10, I have tried also things like : `Round[..., 256 $MachineEpsilon]` and `Round[..., 2^-10]` , without success. `Chop[...]` doesn't seems neither to bring a solution.