Here's our shortlist of the top 5 biggest speed cubes by edge-to-edge measurement - that are mass-produced.
ShengShou 15x15 & MoYu 15x15
120mm
The ShengShou 15x15 and MoYu 15x15 are both 15x15 puzzles, that both measure in at 120mm edge-to-edge length. Both puzzles are available in stickerless only, and both come in highly flashy display cases. However, the ShengShou 15x15 was priced slightly cheaper than the MoYu 15x15, coming in at $279.95 and $299.95 respectively.
ShengShou 17x17
125mm
The ShengShou 17x17 features a new light-weight design which improves the solving experience by making the puzzle easier to handle and turn. Additionally, the Stickerless color scheme features vibrant, easy to distinguish, shades -- all at a lower price point than competitors!
ShengShou 19x19
131mm
The ShengShou 19x19 comes in at a whoppping $999.95 RRP (although on discount now for $649.95). This was the first ever mass-produced 19x19, featuring a stickerless pillowed design, coming with a premium carrying case.
MoYu 21x21
150mm
The MoYu 21x21 comes in at an edge-to-edge length of 150mm, consisting of 2,709 pieces total and wider outer layers for smoother, more controlled turning. The price is pretty hefty for the large puzzle, at $1,499.95.
YuXin HuangLong 17x17
176mm
Despite having a lower layer count than the MoYu 21x21, the HuangLong 17x17, released in late 2017, is a bohemith of a puzzle, the HuangLong 17x17 is shockingly stable and has even withstood drop tests to prove how strong the structure is! The turning is very smooth but we suggest that you ensure that each layer is aligned prior to making a turn.
HeShu 18cm 3x3
180mm
This 3x3 by HeShu measures in 18cm and is currently the World's Largest production cube! It is a very fun novelty item that is also fully-functional.
This puzzle has been popular for novelty solving, and is actually WCA legal - although we don't advise using it if you want the best results for your 3x3 average of course.