The Core Difference: How These Platforms Work
Both systems use lithium-ion cells. The difference is how many cells are wired in series. 20V MAX packs have 5 cells in series. "20V MAX" is peak open-circuit voltage -- the nominal working voltage is 18V, which is why DeWalt tools are compatible with competing 18V ecosystems in terms of cell count (though not physically). 60V FLEXVOLT packs have 15 cells in series at full voltage. But the key innovation is the auto-switching design: the same FLEXVOLT battery reconfigures itself to 3 groups of 5 cells (20V) when inserted into a 20V MAX tool. That's what makes the bridge battery concept work. The result: you can buy a FLEXVOLT battery and run it in every 20V MAX tool you own with no adapters. It just delivers more capacity (runtime) in those tools, not more voltage.When 20V MAX Is Enough
For most homeowners and general DIYers, 20V MAX handles everything:- Drilling into wood, drywall, and light masonry
- Driving screws and fasteners
- Cutting with a circular saw (up to 2x4s easily, sheet goods with a good blade)
- Nailing and stapling
- Most oscillating multi-tool work
- Light-to-medium grinding and cutting
When You Need FLEXVOLT
FLEXVOLT tools are designed around sustained high-draw applications where 20V packs drain fast or throttle under load:- Sustained angle grinding (surface prep, weld removal, cutting metal for extended periods)
- Miter saw work for a full job site day -- the DCW872B FLEXVOLT table saw runs full 8-hour shifts
- Table saw ripping through hardwood or thick material where a 20V saw bogs down mid-cut
- Large reciprocating saw demolition where you're cutting for minutes at a time, not seconds
Battery Compatibility at a Glance
| Battery | 20V MAX Tools | FLEXVOLT Tools | |---|---|---| | 20V MAX 2.0Ah | Yes | No | | 20V MAX 5.0Ah | Yes | No | | FLEXVOLT 6.0Ah | Yes (runs as 20V/6.0Ah) | Yes (runs as 60V/2.0Ah) | | FLEXVOLT 9.0Ah | Yes (runs as 20V/9.0Ah) | Yes (runs as 60V/3.0Ah) | Important: Standard 20V MAX batteries do NOT work in FLEXVOLT-only tools. The connector physically fits, but the tool won't operate. FLEXVOLT batteries always work in 20V MAX tools.FLEXVOLT ADVANTAGE: The Third Option
DeWalt added a wrinkle with FLEXVOLT ADVANTAGE tools -- a subset of 20V MAX tools engineered to extract more power from a FLEXVOLT battery without becoming full FLEXVOLT tools. The DCD999B drill is the best example. On a 20V MAX battery, it outputs 1,000 UWO. Plug in a FLEXVOLT battery, and the tool senses the higher-capacity pack and increases motor output. You get more power without buying a 60V tool. This is the best buy for 20V MAX users who occasionally need more performance: upgrade your battery, not your tool.Cost Comparison
| Item | 20V MAX | FLEXVOLT | |---|---|---| | Entry battery (2.0Ah) | ~$50 | N/A | | Mid battery (5.0Ah) | ~$80 | ~$100 (6.0Ah) | | High-cap battery | $100 (5.0Ah XR) | $149 (9.0Ah) | | Entry drill | $99 (kit) | N/A -- no FLEXVOLT drill | | Heavy grinder | $89 (20V) | $199 (60V, bare) | Bottom line on cost: 20V MAX batteries are significantly cheaper. If you're running a full FLEXVOLT setup alongside 20V MAX, budget at the current retailer price+ per battery. The 9.0Ah bridge battery at the current retailer price is the most cost-efficient way to bridge both systems.Who Should Start With 20V MAX
- Homeowners doing general repairs, projects, and occasional heavy work
- Anyone new to cordless tools -- build the battery collection before adding expensive FLEXVOLT tools
- Budget-conscious buyers -- 20V MAX kits start at the current retailer price with battery and charger included
Who Should Add FLEXVOLT
- Contractors doing sustained heavy work: grinding, large miter cuts, ripping hardwood
- Existing 20V MAX users who find themselves limited by power or runtime in specific applications
- Shop users who want to cut the cord on a table saw or miter saw without losing performance
