Loan Cost Calculator Java Script

This script will allow you and your users to calculate the cost of loan repayments by entering in the specific details.

2 parts to this script - please make sure the copyright note is left intact to the script maker ============================================================================= part 1 - please in head ============================================================================= <SCRIPT LANGUAGE="JavaScript"> /*Cut-N-Paste JavaScript from ISN Toolbox Copyright 1996, Infohiway, Inc. Restricted use is hereby granted (commercial and personal OK) so long as this code is not *directly* sold and the copyright notice is buried somewhere deep in your HTML document. A link to our site http://www.infohiway.com is always appreciated of course, but is absolutely and positively not necessary. ;-) */ <!--Hide JavaScript from Java-Impaired Browsers function test_it(entry) { if (entry.value!=null && entry.value.length!=0) { entry.value=""+ eval(entry.value); } computeForm(entry.form); } function computeForm(form) { if ((form.months.value==null || form.months.value.length==0) || (form.rate.value==null || form.rate.value.length==0) || (form.financed.value == null || form.financed.value.length==0)) { return; } if (!alrt_msg(form.months,1,480,"Your Number of Payments") || !alrt_msg(form.rate,.001,99,"Your Interest Rate") || !alrt_msg(form.financed,100,10000000,"Your Principal Amount")) { form.payment.value="A value out of range - Click Reset"; return; } var i=form.rate.value; ffv=0; ffv+=form.financed.value; fmv=0; fmv+=form.months.value; if (i > 1.0) { // Hack to mostly correct floating point/binary conversion error i=(i/100.0)+.00001; var fmt=""; fmt+=i; fmt=fmt.substring(0,6) form.rate.value=fmt; } i/=12; var isn=1; for (var j=0;j<form.months.value;j++) isn=isn*(1+i); form.payment.value=(form.financed.value*isn*i)/(isn-1); fpv=0; fpv+=form.payment.value; var fmt=""; var add=9; fmt+=form.payment.value; for (var i=0;i<fmt.length;i++) { if (fmt.charAt(i)==".") { add=i+3; i=fmt.length; } } fmt=fmt.substring(0,add); fcalc=((fmv*fpv)-ffv); var fmtb=""; var add=9; fmtb+=fcalc; for (var i=0;i<fmtb.length;i++) { if (fmtb.charAt(i)==".") { add=i+3; i=fmtb.length; } } fmtb=fmtb.substring(0,add); form.payment.value=" $"+fmt+" $"+fmtb; } function reset_it(form) { form.months.value=""; form.rate.value=""; form.financed.value=""; form.payment.value=""; } function alrt_msg(entry,low,high,prompt) { prompt="You couldn't know. "+prompt +" entry has unacceptable stuff: "+entry.value; var scratch=entry.value; for (var i=0;i<scratch.length;i++) { var letter=scratch.substring(i,i+1); if ((letter<"0" || "9"<letter) && letter!='.') { alert(prompt); return false; } } var errtst=parseFloat(scratch) if (errtst<low || high<errtst) { alert("I'm sorry. "+prompt+ " is not in the range" +" from "+low+" to "+high+"!"); return false; } entry.value=scratch; return true; } //--> </SCRIPT> ================================================================================ part 2 - enter this where you want it to show up ================================================================================ <FORM METHOD=POST> <TABLE WIDTH=484 BORDER=2> <TR> <TD COLSPAN=3 VALIGN=TOP ALIGN=CENTER> <B>Simply Complete These Three Columns:</B></TD> <TD VALIGN=TOP ALIGN=CENTER><B>See Your Payment Here</B></TD> <TD VALIGN=TOP ALIGN=CENTER><B>See Your Interest Cost Here</B></TD></TR> <TR> <TD ALIGN=CENTER>Number of<BR>Monthly<BR>Payments</TD> <TD ALIGN=CENTER>Simple<BR>Interest<BR>Rate</TD> <TD ALIGN=CENTER>Principal<BR>Amount<BR>of Loan</TD> <TD ALIGN=CENTER>Your<BR>Monthly<BR>Payment<BR>Will Be</TD> <TD ALIGN=CENTER>Your<BR>Total<BR>Interest Cost<BR>Will Be</TD> </TR> <TR> <TD ALIGN=CENTER> <INPUT TYPE=TEXT NAME="months" SIZE=5 onChange=test_it(this)> </TD> <TD ALIGN=CENTER> <INPUT TYPE=TEXT NAME="rate" SIZE=6 onChange=test_it(this)></TD> <TD ALIGN=CENTER> $<INPUT TYPE=TEXT NAME="financed" SIZE=9 onChange=test_it(this)></TD> <TD COLSPAN=2 ALIGN=CENTER> <INPUT TYPE=TEXT NAME="payment" SIZE=40 onChange=test_it(this)></TD></TR> <TR> <TD COLSPAN=2 ALIGN=CENTER> <INPUT TYPE="reset" VALUE="Click Here to Reset" onClick=reset_it(this.form)></TD> <TD COLSPAN=3 ALIGN=CENTER> <INPUT TYPE="button" VALUE="Click Here to Compute Payment and Cost" onClick=computeForm(this.form)> </TD> </TR> </TABLE></form>