The free archives worth starting with

Le Fauconnier died in 1946, so his work is public domain in most jurisdictions and appears widely on open image libraries. Wikimedia Commons is the densest single source, with reproductions of his major Cubist paintings including works from the years around 1911 and 1912, when he was close to the Puteaux circle. WikiArt indexes a smaller set but organises it usefully by period.

Museum databases are the second stop. Institutions that hold his paintings generally publish at least a thumbnail and a catalogue entry, and some offer high resolution downloads under open access policies. The catch is that no one site aggregates them, so a reverse image search on a specific painting title is often faster than browsing. If a work you want to see is not on Commons, it usually means no open access image exists yet.

For a sense of what his subjects and compositions look like before you go hunting, the overview of Le Fauconnier's most common subjects gives a shortlist of works worth searching by title.

What each source actually gives you

The three main sources differ more in depth than in kind. Commons wins on coverage and image quality but offers little interpretation. WikiArt is lighter on images but easier to scan quickly. Museum collection pages are the most accurate on attribution and dating, which matters for an artist whose oeuvre was catalogued unevenly and whose early work is sometimes confused with that of contemporaries.

Auction archives are the fourth source, and a useful one. Sales catalogues from the past few decades document lesser known canvases, give dimensions and provenance in summary form, and often include a colour reproduction. They are the only place many minor works are visible at all. Treat attributions there with care, as lots are catalogued by auction houses rather than scholars.

If the browsing is a prelude to buying a reproduction, the practical choice between formats is covered in canvas print versus framed poster, and availability questions sit in buying prints without a minimum order.

Why no single archive exists

The absence of a unified collection is not unusual, but it is more pronounced for Le Fauconnier than for his better documented peers. His reputation rests on a short burst of Cubist work in the early 1910s, after which his output and his visibility both thinned. No catalogue raisonné has consolidated the oeuvre, and no foundation holds his estate in the way some contemporaries' estates are held.

That means the honest answer to where to browse is a route, not a destination. Start with Commons for breadth, cross check dates on museum pages, and use auction records for the long tail. Anyone hoping to find a scholar maintained archive will not find one, and any site claiming to be complete should be read with suspicion.

Reproduction sellers draw on the same public domain images, so quality varies with the source file rather than the seller. Auvrique does not currently carry Le Fauconnier editions, and its own archive of available works in the Auvrique archive covers other artists entirely.