UltimaCalc provides a wide variety of formats for displaying numbers and dates.

• Precision can be set to 8, 12, or 16 digits, or be automatic.
• Optionally show digits in groups of 3 or 5 for easy reading.
• Normal, scientific and engineering formats.
• View as hexadecimal

In the normal mode, numbers in the range from 0.001 to just under 10000000000 (or 10¹⁰) are shown in the usual manner. When numbers become very large or very small, a 'scientific' format is more useful. So, for example, a number such as 1.23 x 10⁵⁰ is shown as 1.23e50. You can choose when UltimaCalc should switch to showing numbers in scientific format, or you can have this on all the time, and optionally have the exponent always shown as a multiple of 3.

In the 'Scientific 1' format, numbers are always shown in scientific format, regardless of their value. There is always a single (non-zero) digit before the decimal point. This is illustrated by the image on the right, which also shows that the window's caption can be hidden, for the sake of compactness. (The window can still be dragged, by clicking on the area to the right of the menus.)

The other 'scientific' format, 'Scientific 3' uses a similar format, but the number shown as the exponent is always a multiple of 3. In this format, there can be 1, 2 or 3 digits before the decimal point, depending on the value.

When the precision is set to automatic, the number of digits displayed depends on the width of the window. As many as possible are displayed, up to a maximum of 36, and allowing room for a leading minus sign even if the number is non-negative. UltimaCalc performs calculations at maximum precision regardless of that used for display purposes.

With a very wide window, a long string of digits is displayed. To make these easier to read, they can be shown in groups of three or five digits. Even so, it is often more convenient to display results with fewer digits. You can choose to have only 8 digits, or 12, or 16 displayed. Regardless of the way in which results are displayed, they are always stored internally to their full precision.

Here are some examples illustrating how the result of calculating 8000000/81 is shown in various formats:

Normal (16 digits)	98765.43209876543
Normal, groups of 3 digits	98 765.432 098 765 43
Normal, groups of 5 digits	98765.43209 87654 3
Scientific 1 (12 digit precision, ungrouped)	9.87654320988 e4
Scientific 3 (exponent is always a multiple of 3)	98.7654320988 e3
Engineering (8 digit precision)	98.765432 k

Here at Iconico we do not understand why almost all other calculators seem to consider that hexadecimal numbers are always considered to be integers. This is total nonsense. UltimaCalc can show any number in hexadecimal, complete with digits after a decimal point, and an exponent too, if necessary. The following image shows the approximate value of pi in hexadecimal.

Whilst not actually a display format, UltimaCalc can show numbers approximated as ratios to various degrees of precision. This is particularly useful if you know that the result should be able to be expressed exactly as a ratio. For example, if you calculate 10/7-1/3+1/13 you will notice the digits repeating in a pattern after a certain point. If you try to show the result as a ratio, you will find that all values, even up to a total of 24 digits, are the same, namely 320 / 273.

Different countries have different ideas as to how best to write dates. UltimaCalc allows you to choose whichever formats you wish for entering dates and for showing them. Normally, of course, these two formats would be chosen so as to be compatible with each other.