which iPhone to upgrade to

You can use this comparison page, and check tech specs for your preferred model(s):--> iPhone - Compare Models - Apple

For a quick view (a complete but not detailed list), I suggest that you click/tap on "See all models" in the 1st page.

Regards

Giulio

The only iPhone currently sold that is similar in size to the iPhone 6, is the iPhone SE third generation.

All other options are either larger or smaller than the iPhone SE.

Do note the iPhone 13 mini while physically smaller than the iPhone 6, has a larger screen since it has thinner bezels.

iPhone - Compare Models - Apple

Weight and Dimensions iPhone 6

• Height: 5.44 inches (138.1 mm)
• Width: 2.64 inches (67.0 mm)
• Depth:0.27 inch (6.9 mm)
• Weight: 4.55 ounces (129 grams)

Size and Weight iPhone 14

• Height:146.7 mm(5.78 inches)
• Width:71.5 mm(2.82 inches)
• Depth:7.80 mm(0.31 inches)
• Weight: 172 grams (6.07 ounces)

Size and Weight iPhone 13 Mini

• Height:131.5 mm(5.18 inches)
• Width:64.2 mm(2.53 inches)
• Depth:7.65 mm(0.30 inches)
• Weight: 140 grams (4.94 ounces)

Size and Weight iPhone 13

• Height:146.7 mm(5.78 inches)
• Width:71.5 mm(2.82 inches)
• Depth:7.65 mm(0.30 inches)
• Weight: 173 grams (6.10 ounces)

If you want a similar sized iPhone, go for the iPhone 13 mini. If you want the best smartphone, ultimate iPhone experience, best of the best, go for the iPhone 14 pro. Otherwise, the iPhone 13 mini is a great option. The iPhone 14 pro has the best display in a smartphone, earning the 2022 display mate champion title for how color accurate and in other words, good, the display is. Although, the 13 mini is a great option too. It has a stunning display (in fact, currently using one) with similar size to iPhone 6. It also is mind bogglingly powerful. It’s an excellent phone for making calls, has great battery life, and is the best small smartphone on the market. You will be blown away with the display improvements it has over the 6. It has a Super Retina XDR display, best display technology manufactured for smartphone. It has amazing sharpness and looks stunning, while still maintaining incredibly color accuracy. Going from LCD to OLED will make you never want to go back.