Tax Calculator

https://www.incometaxindia.gov.in/Pages/tax-calculators.aspx?lang=eng

Online Tax payments

https://onlineservices.tin.egov-nsdl.com/etaxnew/tdsnontds.jsp

Know your Pan

https://portal.incometaxindiaefiling.gov.in/e-Filing/Services/KnowYourPanLinkGS.html?lang=eng

Know your TAN

https://portal.incometaxindiaefiling.gov.in/e-Filing/Services/KnowYourTanLink.html?lang=eng

Tax Calendar

https://www.incometaxindia.gov.in/Pages/deadline.aspx?lang=eng

GST Payment link

https://services.gst.gov.in/services/quicklinks/payments

E-Way Bill portal

https://ewaybillgst.gov.in/

MCA portal

http://www.mca.gov.in/