Turn pixels and DPI into a physical print size, and check the ppi on common papers
Print size
508 × 338.7 mm
20″ × 13.3″
Print resolution
300
Pixel size
6000 × 4000
Common papers
A3297 × 420 mm342 ppiExcellent
A4210 × 297 mm484 ppiExcellent
A5148 × 210 mm686 ppiExcellent
A6105 × 148 mm968 ppiExcellent
B5176 × 250 mm577 ppiExcellent
Letter215.9 × 279.4 mm471 ppiExcellent
Legal215.9 × 355.6 mm429 ppiExcellent
5 inch (3.5 × 5 in)89 × 127 mm1140 ppiExcellent
6 inch (4 × 6 in)102 × 152 mm996 ppiExcellent
7 inch (5 × 7 in)127 × 178 mm800 ppiExcellent
8 inch (6 × 8 in)152 × 203 mm668 ppiExcellent
10 inch (8 × 10 in)203 × 254 mm500 ppiExcellent
12 inch (10 × 12 in)254 × 305 mm400 ppiExcellent
Print size = pixels ÷ DPI × 25.4. 300 DPI is the norm for photos and albums; 150 DPI is the floor for large formats viewed from a distance. Below 150 DPI the grain shows up close, and upscaling adds no real detail.