The IRS published various cost of living adjusted numbers for the 2020 tax year in Revenue Procedure 2019-44.[1]

This procedure, published annually, deals with most items that are to be inflation adjusted by law aside from items related to retirement plans and health savings accounts, for which other revenue procedures are published each year. In fact, the retirement plan numbers were published on the same day as this main procedure this year.

Some key numbers in the procedure are:

Tax rate schedules for individuals (all filing statuses) and trusts/estates;
Standard deduction for all filing statuses;
§179 items: Maximum amount that can be expensed will be $1,040,000, while the amount will begin to be phased out when total additions for the year exceed $2,590,000;
Threshold amounts for the qualified business income deduction under §199A will be $326,600 for married couples filing a joint return and $163,300 for all other filing statuses;
Maximum average revenue for use of the cash method of accounting will be $26,000,000;
The threshold for excess business losses will be $259,000 ($518,000 for married couples filing a joint return);
The basic exclusion amount for decedents dying in 2020 will be $11,580,000; and
The annual exclusion for present interest gifts will be $15,000.

The other numbers are found in the Revenue Procedure available at the link provided in the footnotes.

[1] Revenue Procedure 2019-44, November 6, 2019, https://www.irs.gov/pub/irs-drop/rp-19-44.pdf, retrieved November 9, 2019