Downrank calculator
Casting a lower rank can heal for nearly as much and cost far less mana. Pick a spell and your level and see which rank wins.
Setup
From gear and buffs.
Multiplies the whole amount.
Lesser Heal
At level 60, rank 3 gives the most healing per mana (1.99), and it is your highest rank, so there is nothing to save by downranking.
How downranking works
A spell rank heals for a fixed base amount that grows a little with your level, plus a share of your bonus healing (or spell damage) called its coefficient. The coefficient depends on the cast time, not the rank, so a low rank has a small base but soaks up the same share of your gear as a higher one. With enough bonus healing, the cheap rank heals almost as much for a fraction of the mana.
Forever keeps the full coefficient on every rank. Classic Era cut the ranks you learn before level 20 by 3.75% for every level below 20, which is why Lesser Heal rank 1 takes 12.3% of your bonus there and 42.9% in Forever. Talent bonuses multiply the whole amount, base and bonus alike.
The numbers come from the beta client's spell data and can change before launch. Levels above 20 are the client's values, not measured ones.