How to generate random number without duplicates in Excel?
In many cases, you may want to generate random numbers in Excel? But with the general formulas to randomize numbers, there may be some duplicate values. Here I will tell you some tricks to generate random numbers without duplicates in Excel.
Generate unique random numbers with formulas
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Generate unique random numbers with formulas
To generate the unique random numbers in Excel, you need to use two formulas.
1． Suppose you need to generate random numbers without duplicates into column A and column B, now select cell E1, and type this formula =RAND(), then press Enter key, see screenshot:
2. And select the whole column E by pressing Ctrl + Space keys simultaneously, and then press Ctrl + D keys to apply the formula =RAND() to the whole column E. See screenshot:
3. Then in the cell D1, type the maximum number of your needed random number. In here case, I want to insert random numbers without repeated between 1 and 50, so I will type 50 into D1.
4. Now go to Column A, select cell A1, type this formula =IF(ROW()ROW(A$1)+1>$D$1/2,"",RANK(OFFSET($E$1,ROW()ROW(A$1)+(COLUMN()COLUMN($A1))*($D$1/2),),$E$1:INDEX($E$1:$E$1000,$D$1))), then drag the fill handle to next column B, and drag down the fill handle to the range you need. See screenshot:
Now, in this range, the random numbers you need are no repeated.
1. In the above long formula, A1 indicates the cell you use the long formula, D1 indicates the maximum number of the random number, E1 is the first cell of column you apply formula =RAND(), and 2 indicates you want to insert random number into two columns. You can change them as your need.
2. When all the unique numbers are generated into the range, the redundant cells will be shown as blank.
3. With this method, you just can generate random number start from number 1. But with the second way, you can easily specify the random number range.
Generate unique random number with Kutools for Excel’s Insert Random Data
With above formulas, there are too much inconvenience to handle. But with Kutools for Excel’s Insert Random Data feature, you can quickly and easily to insert the unique random numbers as your need which will saves a lot of time.
After installing Kutools for Excel, please do as below:（Free Download Kutools for Excel Now!)
1. Select the range you need to generate random numbers, and click Kutools > Insert > Insert Random Data. See screenshot:
2. In the Insert Random Data dialog, go to the Integer tab, type the number range you need into the From and To text boxes, and remember to check Unique values option. See screenshot:
3. Click Ok to generate the random numbers and exit the dialog.
Insert Random Data Without Duplicate
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