Compatibility guide
SRAM eTap AXS vs Shimano Di2: what crosses over and what doesn't
Both are electronic wireless (or semi-wireless) shifting systems, and both are excellent — but they're built on completely separate, incompatible standards. Here's exactly where the line is.
The short answer
SRAM eTap AXS and Shimano Di2 are not cross-compatible at the shifting level. Different wireless protocols, different pairing apps, different batteries, and (on the drivetrain side) different freehub standards. You build with one groupset's shifters and derailleurs, not a mix. Everything outside the electronic shifting loop — frame, fork, brakes (if you match hydraulic standards), wheels, tires — is a separate compatibility question and isn't affected by this split.
Component-by-component
| Component | Cross-compatible? | Note |
|---|---|---|
| Shifters ↔ derailleurs | No | Different wireless protocols; AXS and Di2 shifters only pair with their own brand's derailleurs. |
| Batteries | No | AXS uses a removable 25g battery; Di2 uses a wired internal battery with its own charger. |
| Pairing / setup app | No | SRAM AXS app vs Shimano E-TUBE — separate ecosystems, no shared configuration. |
| Cassette freehub standard | No | AXS road/gravel cassettes need XDR; Shimano needs HG or HG-L2 (Micro Spline off-road). Different driver body. |
| Chain | No | Each brand's chain is tuned to its own derailleur pulley spacing and shift ramps; cross-brand chains shift poorly even though they physically fit. |
| Crankset / bottom bracket | Yes | BB standards (T47, BSA, PF30, etc.) and chainring bolt patterns aren't shifting-protocol-specific — either brand's crankset works if the BB and chainline match. |
| Brake calipers / rotors | Yes, if standards match | Flat-mount hydraulic and Center Lock/6-bolt rotors are shared industry standards, not brand-locked. |
| Handlebar, stem, seatpost, frame | Yes | No shifting-protocol dependency at all — pick based on fit and the frame's own standards. |
Where it breaks
- An AXS shifter cannot pair with a Di2 derailleur, or vice versa — there's no bridging accessory that makes this work reliably.
- A SRAM AXS cassette needs an XDR freehub body; a Shimano 11/12-speed cassette needs HG or HG-L2. Swapping brands on an existing wheel means swapping the freehub body, not just the cassette.
- Chargers aren't interchangeable — AXS batteries charge off the bike on SRAM's own charger; Di2 charges in-place via a proprietary cable and port.
Practical takeaways
- Switching a bike from Di2 to AXS (or back): plan on replacing shifters, derailleurs, cassette (and possibly the freehub body), and chain as a set — not a piecemeal swap.
- Buying a frameset: almost every current road/gravel frame is groupset-agnostic for cable-free electronic shifting, so the brand decision doesn't limit your frame choice.
- Wheels: if you're set on a wheelset, check whether it ships with (or can take) both XDR and HG-L2 driver bodies before committing to a groupset brand.
Check a specific pairing
Got a specific part number in mind? Drop it into the compatibility checker for a verdict with reasoning, or spec a full build in the planner.