Aspect Ratio Calculator

9:16 Aspect Ratio: Vertical Video Sizes for TikTok, Reels and Shorts

The calculator is preset to 9:16. Use section 1 to check what ratio your source footage really is, and the preview to see exactly what a vertical crop would cost it.

1 · Find a ratio from pixels

16:9= 1.7778:1 · landscape

Exact match for the standard 16:9 ratio.

2 · Resize with a locked ratio

Ratio (custom allowed)
:

= 9:16 · 0.5625:1

New size (edit either side)
×

width × height, px

Exact fit — both sides are whole pixels at this ratio.

3 · Preview: your pixels inside the locked ratio

Content 1920×1080 (16:9) placed in a 9:16 frame:

68.4% of the frame height becomes top/bottom bars.

9:16 export sizes

The three big vertical platforms — TikTok, Instagram (Reels and Stories) and YouTube Shorts — all recommend the same upload size: 1080×1920. That convergence makes the rest of the ladder simple; every useful 9:16 size is a clean multiple or fraction of it:

The 9:16 ladder. All rows are exactly 9:16 — every width is the height × 0.5625.
Resolution Name Megapixels Notes
540×960 qHD vertical 0.52 Low-bandwidth previews; half of 1080×1920 per side
720×1280 720p vertical 0.92 Acceptable minimum for most vertical feeds
1080×1920 Full HD vertical 2.07 The standard export for TikTok, Reels and Shorts
1440×2560 QHD vertical 3.69 ×1.33 of standard; platforms typically re-encode down
2160×3840 4K vertical 8.29 Future-proof master copies; ×2 of standard per side

Worked example: what cropping 16:9 to 9:16 really costs

Say you shot 1920×1080 landscape and want a vertical cut. A center crop keeps the full 1080 height, and the width becomes 1080 × 9 ÷ 16 = 607.5 → 608 px. You keep a 608×1080 sliver — just 31.6% of the original width; the remaining 68.4% is discarded. Set the calculator's section 1 to 1920×1080 with the 9:16 preset and switch the preview to "Crop" to see this drawn to scale: the dimmed area is what your viewers never see.

The alternative, letterboxing, has the mirror-image price: the full 16:9 frame fits in the vertical canvas, but it occupies only 31.6% of the frame height — the other 68.4% is bars (which some creators fill with captions or a blurred copy of the footage). Neither option is free; 9:16 simply punishes landscape sources harder than any common conversion because the two ratios are so far apart.

Worked example: upscaling 720p vertical

Old vertical footage at 720×1280 converts to the standard 1080×1920 with a clean ×1.5 factor on both sides. That is a real upscale — the encoder invents pixels — but the ratio is identical, so there is no cropping or distortion involved. Lock 9:16 in the calculator and type 1080 as the width; the height lands on exactly 1920 with the "exact fit" note, confirming both sides are whole pixels.

Related pages

Going the other direction — vertical source to a horizontal player — is the same math with the roles swapped; run it on the main aspect ratio calculator. Instagram's feed also accepts a gentler portrait format that keeps far more of a landscape photo: see the 4:5 Instagram portrait page. And if you are checking what ratio a source file actually is before deciding, the pixels-to-ratio lookup does the reverse calculation. The horizontal standard itself is covered on the 16:9 resolution chart.

Frequently asked questions

What size should I export vertical video?

1080×1920 is the safe answer for every major vertical feed — TikTok, Instagram Reels and Stories, and YouTube Shorts all recommend it. Exporting larger (1440×2560 or 2160×3840) is not wrong, but expect the platform to re-encode it down to roughly Full HD delivery anyway.

Can I just crop my 16:9 footage to 9:16?

You can, but do the math first: a center crop keeps only 31.6% of the frame width — 608 of 1920 pixels. Anything near the left or right edges is gone. That is why the practical advice is to shoot vertical for vertical, or at least frame your 16:9 shots with all action dead-center if a vertical cut is planned.

Why 608×1080 and not 607×1080 or 607.5?

A 9:16 crop of a 1080-tall frame is exactly 1080 × 9 ÷ 16 = 607.5 px wide. Half pixels do not exist, and video encoders generally want even dimensions anyway. Round-half-to-even sends 607.5 to 608 (the even neighbour), which conveniently is also encoder-friendly. The calculator shows the exact value and the rounding whenever this happens.

Where is it safe to put text in a 9:16 video?

Every platform overlays its own UI — captions, buttons, usernames — near the bottom and along the right edge, and the exact overlay zones differ by app and change with redesigns. The robust habit is to keep essential text and faces near the center of the frame and check the platform's own preview before publishing, rather than trusting any fixed pixel template.