If there's one thing your competitor probably isn't doing, when it comes to online tools, it's accepting fractions for numeric input.
For instance, if you have a tool that calculates the square footage of a room, why not allow the user to enter:
Width: 5 3/4
Length: -2 3/8
Using ColdFusion for our example, by running your fields through a loop and detecting the presence of a "/" in the input, we can convert the value to a decimal number for use in our processing script:
<cfloop collection="#url#" item="key">
<cfif Find("/", url[key])>
<cfset url[key] = trim(url[key])>
<cfset frac = ListLast(url[key], " ")>
<cfif frac eq url[key]><cfset url[key] = 0></cfif>
<cfif Left(url[key], 1) neq "-">
<cfset url[key] = Val(url[key]) + Evaluate(frac)>
<cfelse>
<cfset url[key] = Val(url[key]) - Evaluate(frac)>
</cfif>
</cfif>
</cfloop>