Bird watching binoculars

Match magnification to where you bird

Choose by habitat: lower power for woods and close birds, higher power for open water and distant birds. Our magnification guide favors 7x in dense forest and 10x for wetlands and meadows, and Cornell Lab suggests 10x for shorebirds, raptors and seabirds.

How wide a field of view to look for

Look for a field near the top of the birding range, which Cornell Lab puts at about 5.5 to 8.5 degrees (290 to 470 ft at 1,000 yards). Each extra half degree shows roughly 8% more width.

In this list Nikon gives 420 ft for the Monarch 7 8x42 and 293 ft for the Prostaff 5 10x50.

Full-size, compact or pocket

The second number in the size tells you the class: about 42 mm is full-size, 32 mm compact and 25 mm pocket, as Cornell Lab groups them. Our compact birding guide compares the smaller pairs.

Sizes of the listed models

The table counts the listed models by size, with exit pupil (lens diameter divided by magnification) as a guide to brightness at dawn and in shade.

Brightness for dawn and deep shade

A bigger exit pupil gives a brighter view in poor light: 5.25 mm for 8x42, 4 mm for 8x32 and about 3.1 mm for 8x25. Audubon adds that lenses under 30 mm are not bright enough to show detail in poor light.

How much weight to carry on a long walk

Aim for a pair you will keep around your neck all day. Cornell Lab puts a typical 8x42 at about 1.6 pounds and compacts nearly half a pound lighter, and suggests a harness to spread the load of a heavy pair.

Listed weights here run from about 8.5 oz for the Leica Ultravid BR 8x20 to 31.7 oz for the Nikon Aculon A211 10x50.

Waterproof ratings for rain and boat trips

Check the maker's stated rating, because waterproofing ranges from none to submersion. Leica rates the Ultravid BR 8x20 to 5 m and Swarovski the CL Pocket 10x25 to 4 m, while Celestron lists the UpClose G2 10x50 as water resistant and Bushnell lists the PowerView 10x42 as not waterproof.

In this list, Vortex states that the Crossfire HD 8x42 is fogproof, nitrogen gas purged and O-ring sealed, and Nikon lists the Action EX 7x35 as nitrogen filled and O-ring sealed.

Try the fit in your own hands

Hold a pair before buying if you can; it is Cornell Lab's top tip. Check that the focus wheel turns smoothly, the eyecups click and stay put, and the edges do not roll or distort when you scan.

Check the specs of the exact variant

Read the maker's figures for the size you are buying, since one family can differ by variant. Maven lists 19.5 mm eye relief for its C.1 8x42 and 16 mm for the 10x42.