A DeWalt FlexVolt battery is the one pack that runs both 20V MAX and 60V MAX tools. Slide it onto a 20V MAX tool and it operates at 20 volts; slide it onto a 60V MAX tool and it switches up to 60 volts automatically, thanks to what DeWalt calls “patented technology that automatically switch[es] voltages when you change your tools.” That is the core compatibility story: one battery, two voltage classes, no adapter.
DeWalt’s own FLEXVOLT Battery System page backs this up directly, stating that you can “Power your DEWALT 20V MAX* and 60V MAX* power tools with FLEXVOLT® batteries,” and that “FLEXVOLT® batteries are compatible with DEWALT 20V MAX* power tools.” In other words, FlexVolt is backward-compatible into the 20V MAX line by design. If you are already invested in DeWalt’s 20V MAX platform and add a 60V MAX tool later, you do not need to start a separate battery collection — you need at least one FlexVolt pack.
What about a standard 20V MAX battery in a 60V tool?
This is where it gets more careful. None of DeWalt’s own pages explicitly says whether a standard, non-FlexVolt 20V MAX battery works in a 60V-MAX-only tool. Third-party sites commonly claim it will not, but those claims were not traced to a verbatim DeWalt statement, so we are not presenting them as fact here. DeWalt simply does not confirm the compatibility one way or the other in its official materials.
That gap matters because it is easy to assume the battery will at least fit and run. The safer reading is that a 60V MAX tool is engineered around the FlexVolt pack, and DeWalt has not verified that a standard 20V MAX battery will deliver what the tool needs. If you are standing in the aisle deciding what to buy, do not count on a regular 20V MAX battery powering a 60V-only tool.
FLEXVOLT ADVANTAGE is a separate idea
DeWalt also sells 20V MAX tools labeled FLEXVOLT ADVANTAGE. This is not the same as a 60V MAX tool, and it does not apply across the entire 20V MAX lineup. DeWalt’s FLEXVOLT ADVANTAGE page says “This advanced technology makes our new 20V MAX* Circular Saw, Angle Grinder, Reciprocating Saw, and Hammer Drill more powerful than ever before,” and that it is “Compatible with all DEWALT 20V MAX* and 20V/60V MAX* FLEXVOLT® batteries.”
Those four categories — circular saw, angle grinder, reciprocating saw, and hammer drill — are the only ones DeWalt confirms for FLEXVOLT ADVANTAGE. If you own one of those four tools, pairing it with any DeWalt 20V MAX battery or a FlexVolt battery unlocks the extra performance the label promises. We are not extending that claim to other 20V MAX tools; DeWalt did not.
Capacity and lineup
For 60V MAX performance, DeWalt points to its FlexVolt battery lineup. The 60V MAX System page says “60V MAX* tools combined with 20V/60V MAX* FLEXVOLT® Batteries provide maximum performance,” and notes that “20V/60V MAX* FLEXVOLT® Batteries are available in 6AH, 9AH, 12AH and 15AH.” The DCB606 FlexVolt 20V/60V MAX 6Ah Battery page lists “6ah capacity,” compatibility with “20V MAX* and 60V MAX* tools,” and the automatic voltage switching behavior.
One detail worth flagging: the DCB606 product page does not break out a separate Ah rating for 60V-mode operation. Any “equivalent” capacity figure you see floating around online is not coming from DeWalt’s own product page, so treat it accordingly.
Practical takeaway
If you own or are buying any 60V MAX tool, you need a FlexVolt battery. A standard 20V MAX battery is not confirmed by DeWalt to work in a 60V-only tool, so do not assume it will. If you are staying entirely within 20V MAX tools, a FlexVolt battery still works fine — it auto-switches down — but you are paying for capability you do not need unless you also own 60V gear. The four FLEXVOLT ADVANTAGE tools — circular saw, angle grinder, reciprocating saw, and hammer drill — are the middle ground: pairing any of them with any 20V MAX or FlexVolt battery unlocks extra power, which is worth knowing if you own one of those four specifically.
How this was checked
Facts on this page are drawn from DeWalt’s own FLEXVOLT Battery System, FLEXVOLT ADVANTAGE, 60V MAX System, and DCB606 FlexVolt 20V/60V MAX 6Ah Battery product pages.
Sources checked: 2026-08-11. A new review date will only be set after the linked pages are re-checked.