which kind of drywall or hollow wall anchor comes in the largest diameter?

The hollow‑wall anchors that come in the largest diameters are generally heavy‑duty toggle‑style or specialty “plasterboard” anchors that use a relatively large drill hole (often 1/2 in or more) and a large bolt or screw (up to about 3/8 in).

Anchor types and diameters

• Standard plastic or self‑drilling drywall anchors are usually small, with typical outside diameters around 1/4 in to 5/16 in and matched to #6–#8 screws.

• Heavy‑duty metal toggle bolts and similar toggle‑style anchors are sized by the bolt diameter , often 1/4 in or 3/8 in, and require significantly larger holes than plastic anchors.

Largest “common” options

• Conventional toggle bolts in the consumer range go up to about 3/8 in bolt diameter, and require a hole larger than the bolt—commonly around 1/2 in or more.

• Some modern toggle‑style drywall anchors are sold specifically as “large toggle” anchors and specify hole sizes around 3/8 in for #8 screws, already larger than most plastic anchors.

Specialty heavy‑duty anchors

• Specialty high‑capacity plasterboard anchors (often European or pro‑grade brands) may be rated for very high loads and use large drill bits or spade bits, again in the 1/2 in range or higher, to accept large screws or bolts.

• These systems are effectively hollow‑wall anchors but start to overlap with light framing/through‑bolting practice, where the limiting factor is the wall, not the anchor diameter.

Practical takeaway

• If your goal is “largest diameter” in a normal DIY context, heavy‑duty toggle bolts (up to about 3/8 in bolt size) and large toggle‑style drywall anchors are as big as it gets before you move to framing or structural attachment methods.

• For very heavy items, anchoring into studs or using a rail system is usually safer than trying to push drywall or hollow‑wall anchors beyond those sizes.

Information gathered from public forums or data available on the internet and portrayed here.