Mega Backdoor Roth Calculator

Step 1: Max out pre-tax/Roth employee contributions ($24,500)
Step 2: Make after-tax contributions up to the $72,000 total limit
Step 3: Convert after-tax balance to Roth (in-plan or rollover)

Calculate after-tax 401(k) contributions and Roth conversion potential

The mega backdoor Roth lets you contribute up to $72,000 total to your 401(k) in 2026 by using after-tax contributions, then converting them to Roth. This advanced strategy requires a plan that allows after-tax contributions and in-plan Roth conversions.