1. Following is the oligocalc software which can be used to calculate Tm, to check self complementarity etc http://biotools.nubic.northwestern.edu/OligoCalc.html

2. If you are having sequence you can use NCBI primer designing tool also the link is http://www.ncbi.nlm.nih.gov/tools/primer-blast/.

3. Sometimes I prefer CLC workbench also, but it depends if you need to add any restriction site to it.

All the best Ripon.

There is a very useful software you can use online to do it. 

Even you can use real time PCR

If you have problem we can do it....

http://www.sigmaaldrich.com/technical-documents/articles/biology/oligoarchitect-online.html

Thank you Ashish and António. when I go for downloading FASTA sequence, there is a list of sub genotype sequence of a particular gene. How could I select wild type sequence. Please tell me are these links use full for cross checking the primer, I mean to say whether the primers are correctly designed or not for particular gene?