Pending or Processing?
If Pending, when did you e-file the tax return? It can take from 24 to 72 hours after filing before the tax return will either be Accepted or Rejected by the tax authority.
Pending simply means that your e-filed return is on its way and that the government hasn't accepted or rejected it yet.
After the tax return has been Accepted by the IRS (meaning only that they received the return) it will be in the Processing mode until the tax refund has been Approved and then an Issue Date will be available on the IRS website.
See this IRS website for federal tax refund FAQ's - https://www.irs.gov/refunds/tax-season-refund-frequently-asked-questions
