Hi
I am F-1 visa student, currently on OPT working in Maryland. My total income for an year is $48,000.
I would like to know tax percentage for opt students on both federal and state tax(MD).
Should I have to pay for ssn and medicare. Please let me know.
I appreciate your help. Thanks.

You are EXEMPT from FICA (Social security and Medicare) taxes due to your F-1 visa status. If your employer is withholding these taxes, download IRS Pub 519 and show him pages 54-55 to get a refund from the employer. If he refuses to cooperate, get a refusal letter and contact me about submitting Forms 8316 and 843 to get the refund from the IRS.

You are squarely in the 15% tax bracket for the IRS and about 6% for Maryland.

Thank you for giving me information. Is the 15% of federal you have mentioned here is for four weeks or two weeks payment. Because, right now I have been deducted 13% of federal and 7% of state on a semi month basis(two weeks). Is the federal and state tax deductions are same for H-1 and F-1 visas. If am eligible for a lower tax deductions, please provide me where I can get the proof for it, so that I can give it to my employer. Please let me know. Thanks

International students pay the same tax rates as U.S. citizens.

The tax exemption for FICA can be found on IRS Pub 519, pages 54-55, which can be downloaded from Internal Revenue Service.