Skip to content
The Cam Feeder

Smart Bird House Cameras

Nest Box Hole Sizes

The most consequential measurement in this hub, and it is not a camera specification. An eighth of an inch decides which birds can use the box and which ones can take it from them.

Close-up of the entrance hole on a wooden nest box

How this page is funded. Buying through a link here earns us a commission at no extra cost to you. It does not change what we recommend or the order we recommend it in, and we have not handled any of these products ourselves - see how we pick and the full disclosure.

If you read one page in this hub, make it this one. The entrance hole diameter matters more to what you will film than every camera specification combined, and it is the thing buyers pay least attention to.

Why an eighth of an inch matters

A nest box hole is a filter. Any bird that physically fits can use the box; any bird that does not, cannot. That is the entire mechanism, and it is remarkably precise - the difference between a box that houses chickadees and a box that houses house sparrows can be an eighth of an inch.

This matters beyond simply choosing your species, because of competition. House sparrows and European starlings are non-native, aggressive cavity nesters, and they will evict native birds from a box - destroying eggs and killing nestlings in the process. They are also, being non-native, not protected in the United States in the way native migratory birds are.

A correctly-sized hole is the main defense against that. Too large, and the box you installed for chickadees becomes a starling box - and you will have installed a camera to film it happening.

Hole sizes by species

Common North American cavity nesters and their entrance hole diameters
SpeciesHole diameterNotes
Black-capped / Carolina chickadee1 1/8"Small enough to exclude house sparrows, which is the main reason to choose it.
House wren1 1/8"Will use a range of sizes; the small hole keeps competitors out.
Tufted titmouse1 1/4"A common feeder visitor that will also use a box.
White-breasted nuthatch1 1/4"Also uses a similar hole to the titmouse.
Eastern bluebird1 1/2"The classic nest box species. A round 1 1/2" hole is the standard.
Western / mountain bluebird1 9/16"Slightly larger than the eastern species.
Tree swallow1 3/8" to 1 1/2"Overlaps with bluebirds and often competes for the same boxes.
Downy woodpecker1 1/4"Will use a box packed with wood shavings.
Northern flicker2 1/2"Much larger box and hole; also admits starlings, which is unavoidable at this size.
Screech owl / American kestrel3"A different scale of box entirely, and a genuinely different project.
Common North American cavity nesters and their entrance hole diameters

Quick picks

Ranked on published specifications and what each one costs to own. Every pick names the buyer it is wrong for.

Ranked on published specifications and what each one costs to own. Every pick names the buyer it is wrong for.
#ProductBest forPrice
1
No image

Netvue Birdfy Nest (dual-cam)

Two 1080p cameras - one in the nest chamber, one on the entrance - with infrared and a 60 degree adjustable angle. This is the whole nesting season.

Inside the box and outside it, at once
Check price on Amazon

#ad No live price right now. How this is funded

2
No image

Euphoricca Smart Bird House

3MP with full-color night vision rather than infrared gray - a real difference on a subject that is only ever in the dark.

Color at night inside the box
Check price on Amazon

#ad No live price right now. How this is funded

3
No image

Birdfy Smart Bird House (Lifetime AI)

Auto-records the nesting stages and flags them, with lifetime AI and a remote control so you never have to open the box.

Nesting-stage alerts, paid once
Check price on Amazon

#ad No live price right now. How this is funded

No image

1. Inside the box and outside it, at once

Netvue Birdfy Nest (dual-cam)

Two 1080p cameras - one in the nest chamber, one on the entrance - with infrared and a 60 degree adjustable angle. This is the whole nesting season.

Check price on Amazon

#ad No live price right now. How this is funded

A nest box camera is a completely different proposition to a feeder camera and it is worth understanding before you buy. A feeder gives you a hundred short visits a day. A nest box gives you nothing for weeks, then one continuous story - building, laying, hatching, fledging - that runs for about six weeks and does not repeat until next year. See what you actually see in a nest box.

The inside camera plus infrared is the whole product. Nest chambers are dark by design, and without IR the interior camera would show you nothing for the two weeks that matter most.

What is not published is the entrance hole diameter, and that is the specification that decides everything. Hole size is what selects your tenant - and gets it wrong. Hole size by species has the numbers; measure the box when it arrives.

Subscription offered, price not published on the listingNo species count published2 specs the maker will not publish
Published specifications for the Netvue Birdfy Nest (dual-cam)
CamerasTwo: one inside the chamber, one facing the entranceSource: Birdfy Nest - manufacturer listing on Amazon, retrieved 1 September 2026
Video resolution1080p FHD on both camerasSource: Birdfy Nest - manufacturer listing on Amazon, retrieved 1 September 2026
Night visionInfraredSource: Birdfy Nest - manufacturer listing on Amazon, retrieved 1 September 2026
Camera angle60 degrees adjustable on bothSource: Birdfy Nest dual-cam - manufacturer listing on Amazon, retrieved 1 September 2026
AudioBuilt-inSource: Birdfy Nest dual-cam - manufacturer listing on Amazon, retrieved 1 September 2026
SolarSolar poweredSource: Birdfy Nest - manufacturer listing on Amazon, retrieved 1 September 2026
Entrance hole diameterNot publishedThis is the specification that decides which species can use the box.
Battery capacityNot published

What it does well

  • Two cameras cover the chamber and the entrance simultaneously
  • Infrared, which is the only way the interior camera is useful
  • Built-in audio - nestlings are far louder than people expect
  • Solar, which matters for a box you must not disturb once occupied

What it does not

  • Entrance hole diameter is not published, and it decides which species can nest
  • 1080p on both cameras, with no higher option
  • A nest box is empty most of the year

Skip this: if you want something to watch year-round. A nest box is spectacular for six weeks and inert for the other forty-six; a feeder camera is the opposite trade.

No image

2. Color at night inside the box

Euphoricca Smart Bird House

3MP with full-color night vision rather than infrared gray - a real difference on a subject that is only ever in the dark.

Check price on Amazon

#ad No live price right now. How this is funded

Full-color night vision inside a nest chamber is a bigger deal than the same feature outdoors. The interior of a box is dark essentially all the time, so an infrared camera renders the entire nesting season in gray. Color shows you egg markings and nestling plumage as they develop.

3MP is modest, but a nest box camera sits four inches from its subject. Resolution matters far less at that distance than it does on a feeder perch six feet away.

Single camera, so you get the chamber or the entrance, not both. The Birdfy Nest is the dual-camera answer.

The listing says nothing about a subscriptionNo species count published4 specs the maker will not publish
Published specifications for the Euphoricca Smart Bird House
Photo resolution3MP HDSource: Euphoricca bird house - manufacturer listing on Amazon, retrieved 1 September 2026
Night visionFull colorColor rather than the infrared gray most of this category uses.Source: Euphoricca bird house - manufacturer listing on Amazon, retrieved 1 September 2026
CaptureAuto capture with motion detection, app controlSource: Euphoricca bird house - manufacturer listing on Amazon, retrieved 1 September 2026
Entrance hole diameterNot published
Battery capacityNot published
Wi-Fi bandNot published
Species identifiedNot published

What it does well

  • Full-color night vision, unusual on an interior nest camera
  • 3MP at four inches is more than adequate
  • Simple single-camera setup

What it does not

  • One camera, so no entrance view
  • No published hole diameter, battery or Wi-Fi band
  • No stated identification capability

Skip this: if you want the entrance activity as well as the chamber. Half the nesting story happens at the hole.

No image

3. Nesting-stage alerts, paid once

Birdfy Smart Bird House (Lifetime AI)

Auto-records the nesting stages and flags them, with lifetime AI and a remote control so you never have to open the box.

Check price on Amazon

#ad No live price right now. How this is funded

Nesting-stage detection is the one AI feature in this whole category that is unambiguously worth having. You cannot watch a nest box continuously for six weeks, and the moments that matter - first egg, hatch day, fledging - last minutes. A system that flags them is the difference between seeing the season and missing it.

The remote control deserves more credit than it gets. Opening an occupied nest box can cause abandonment. Being able to change a setting from ten feet away means you never have to weigh a settings change against the birds.

Hole diameter is still unpublished. Same caveat as every box in this category: measure it, then read hole size by species.

No subscription claimed on the maker's listingNo species count published2 specs the maker will not publish

What it does well

  • Nesting-stage alerts - the most genuinely useful AI feature in this category
  • Remote control means the box never has to be opened once occupied
  • Lifetime AI with no subscription
  • Battery and solar

What it does not

  • Entrance hole diameter not published
  • No published battery capacity
  • Nesting-stage detection is only exercised for a few weeks a year

Skip this: if you have not yet worked out which species you are trying to attract. Install timing and hole size decide whether anything moves in at all, and no camera compensates for an empty box.

What to check on a camera nest box

Most camera nest boxes publish a hole size, and it is usually the general-purpose measurement. Before ordering, decide which species you actually want and check the box matches - it is far easier to buy the right hole than to modify one afterwards, and enlarging a hole is a one-way operation.

If a listing does not publish the hole diameter at all, that is a meaningful omission on the single most consequential dimension of the product, and we would treat it the way we treat every other unpublished specification in the roundup: as a gap rather than a detail.

The other dimensions that matter

  • Interior floor size. Roughly 4x4 inches suits chickadees and wrens; around 5x5 suits bluebirds. Too large a cavity is harder for the birds to keep warm.
  • Depth below the hole. Six to eight inches from the hole down to the floor for most small species. Too shallow puts nestlings within reach of a predator at the entrance.
  • No perch. A perch below the entrance is purely decorative and actively harmful - it gives predators and competing birds something to hold onto. Boxes sold with perches are designed for buyers rather than birds.
  • Ventilation and drainage. Gaps near the top and holes in the floor. A sealed box overheats in summer sun and holds water after rain.

Where the box goes

Covered properly in the installation guide, but the short version: mount it on a smooth pole with a predator baffle rather than on a tree trunk, at roughly five to six feet, facing away from prevailing weather and out of full afternoon sun. And put it up in autumn or winter, not spring - birds choose sites well before they lay.

Questions people actually ask

What size hole for a bluebird house?

1 1/2 inches for eastern bluebirds, 1 9/16 inches for western and mountain bluebirds. This is also the default on most commercial camera boxes.

What hole size keeps house sparrows out?

1 1/8 inches. That admits chickadees, wrens and other small cavity nesters while excluding house sparrows, which is the main reason to choose the smaller hole.

Should a nest box have a perch?

No. A perch below the entrance gives predators and competing birds something to grip. Boxes with perches are designed to appeal to buyers rather than to suit birds.

Can I make the hole bigger later?

You can, and it is one-way - so start small. It is much easier to enlarge a hole than to shrink one, and the small hole is the one that excludes aggressive competitors.

How deep should the box be?

Six to eight inches from the bottom of the entrance hole to the floor for most small species. Shallower than that puts nestlings within reach of anything at the entrance.

Sources