Post-money valuation is the total value of a company immediately after it has received a new round of investment.
Quick Reference
Post-money Valuation. Total Value. Pre-money + New Investment.
Expanded Definition:
The post-money valuation is a simple mathematical equation: the pre-money valuation plus the total amount of new capital raised in the current round (Post = Pre + Investment). This figure is used to calculate the percentage of ownership held by new and existing shareholders. For example, if a company has a pre-money valuation of $4 million and raises $1 million, the post-money valuation is $5 million, and the new investors own 20% of the company.