Instagram Post vs Reel Aspect Ratio & Dimensions (2026)

Instagram Feed Posts support Square (1:1 - 1080x1080) and Portrait (4:5 - 1080x1350). Instagram Reels use full-screen vertical (9:16 - 1080x1920) to maximize mobile immersion.

Instagram Post (4:5 / 1:1)

Instagram Post (4:5 / 1:1) (4:5)
1920 x 10804:5 (0.800:1)
Scale Ratio: 0.8000Orientation: Portrait

Instagram Reel (9:16)

Instagram Reel (9:16) (9:16)
1920 x 10809:16 (0.563:1)
Scale Ratio: 0.5625Orientation: Portrait

Side-by-Side Specification Matrix

Feature / SpecInstagram Post (4:5 / 1:1)Instagram Reel (9:16)
Aspect Ratio4:5 Portrait or 1:1 Square9:16 Vertical Full Screen
Optimal Resolution1080 x 1350 px (4:5) / 1080 x 1080 px (1:1)1080 x 1920 px (9:16)
Feed Display AreaCenter Feed CardFull Mobile Viewport + Feed Tab
Content TypePhotos, Carousels, Short ClipsShort-Form Immersive Video

Instagram Post (4:5 / 1:1) Breakdown

PROS

  • High visual sharpness without UI button overlaps
  • Ideal for photo carousels and infographics

CONS

  • Does not fill full mobile screen

Instagram Reel (9:16) Breakdown

PROS

  • Fills 100% of mobile screen for maximum retention
  • Favored heavily by Instagram discovery algorithm

CONS

  • Bottom and right edges overlap with UI buttons and text overlays

Which Should You Choose?

Choose Instagram Post (4:5 / 1:1) If:

  • You are sharing high-res photography, infographics, or carousels

Choose Instagram Reel (9:16) If:

  • You are sharing engaging short videos to reach new audiences

Comparison FAQs

Will Instagram crop a 16:9 video in Reels?

Yes! Instagram Reels forces a 9:16 vertical ratio. Horizontal 16:9 videos will be cropped or pillarboxed.