The width names only part of the capacity
A Speedy 25 is 25 cm wide, 19 cm high and 15 cm deep. The Keepall 45 is 20 cm wider, 8 cm taller and 5 cm deeper, which changes volume far more than the 20 cm width difference suggests. A Neverfull MM has a 31 cm width but only a 14 cm depth, so it carries more like an open tote than a 30 cm Speedy. Place the three dimensions beside your intended contents. Width alone cannot distinguish a soft everyday body from a structured travel bag.
Handles, straps and opening geometry
A Speedy has short top handles and a zipped opening; a Keepall adds handles and a bandoulière strap; a Neverfull uses long side straps and an open top. The clear handle drop belongs to the exact model, because total handle length includes the curve and attachment points. A shoulder tote and hand-carry bag can share the same canvas yet sit differently. Ask for the clear distance under the top handle and for the opening width at its narrowest point. Those figures explain how the bag goes on and what enters easily.
Canvas is a construction, not a one-size stability promise
Monogram and Damier canvases are coated materials built for a structured or semi-structured body, but the leather trim and bag construction decide how the shape behaves. A rolled leather handle, a reinforced base and a zipper change the way the bag stands when full. The visual pattern does not reveal whether the base is reinforced or how the side panels fold. Inspect the base, trim and interior from several angles. A catalogue image that only shows the patterned front can hide a soft or unstructured side that changes capacity under weight.
Compare a daily bag with a travel body
Speedy 25 is compact enough for a phone, wallet, keys and a compact; Speedy Soft 30 adds room for a folded scarf or small pouch. CarryAll PM and Neverfull MM move toward everyday tote duty. Keepall 45 is visibly a travel or weekend shape, with depth and height intended for clothing or bulky soft items. Do not select a Keepall because its 45 cm width resembles a large tote: the role, handles and opening are different. The model name describes the construction, and the dimensions confirm it.
The source-backed measurement request
Send the model reference, width across the base, height to the top edge, depth at the widest point, handle drop and strap drop if present. For a zipped bag, include opening length; for an open tote, include the widest and narrowest top widths. Add photographs of the front, base and interior. This makes a canvas bag query specific enough to compare with the published models in the table, rather than letting a familiar pattern stand in for all six shapes.