https://www.taxact.com/tools/tax-bracket-calculator
https://www.irs.gov/individuals/refund-timing
https://www.irs.gov/filing/wheres-my-amended-return
The recommended and best way to check on a refund status is to go :
PLEASE NOTE – The IRS advises that you check if you haven't received your refund three weeks after your return is electronically filed.
https://www.irs.gov/businesses/small-businesses-self-employed/how-long-should-i-keep-records
Here's what you need to know about the new IRS proposed W-4 design for 2020.
FAQS on the draft 2020 Form W-4