RevenueLab.fyi
Revenue Rex logo mark
🧰 Other · Rex's Toolbox

Aspect Ratio Calculator

Resize to any ratio and see the crop or letterbox you'll get.

Revenue Rex peeking

Rex says

Everyday utility math — the kind you'd otherwise pull up four browser tabs for. I keep it to one clean answer.

Try a scenario

Click to load — tweak from there.

Inputs

Result

Height at your scaled width (px)

1920

Crop-to-fill width (px)

608

Crop-to-fill height (px)

1080

Frame area lost to crop

68.4%

Source ratio (decimal)

1.778

If you letterbox instead

Bars top & bottom if fitting whole frame

Revenue Rex peeking

Psst — share this and help Rex grow

One click, a permanent link with your numbers baked in.

More other

How to use this

  1. 1Enter source width (px).
  2. 2Enter source height (px).
  3. 3Enter target ratio.
  4. 4Enter scale to width (px).
  5. 5Read your height at your scaled width (px) on the right — it updates as you type.
  6. 6Hit Share to keep the scenario or send it to someone.

About this calculator

Fitting a 16:9 master into a 9:16 vertical or a 1:1 square always costs something — either cropped edges or letterbox bars. This shows the new dimensions and exactly how much of the frame you lose.

FormulaHeight = width ÷ ratio; crop loss = 1 − (fitted area ÷ source area).

Worked example

Using the values the calculator loads with:

Inputs

  • Source width: 1920 px
  • Source height: 1080 px
  • Target ratio: 9:16 — Shorts, Reels, TikTok
  • Scale to width: 1080 px

Results

  • Height at your scaled width (px): 1,920
  • Crop-to-fill width (px): 608
  • Crop-to-fill height (px): 1,080
  • Frame area lost to crop: 68.4%
  • Source ratio (decimal): 1.778
  • If you letterbox instead: Bars top & bottom if fitting whole frame

What each field means

Inputs

Source width (px)
The source width used in the calculation, measured in px. Starts at 1920 px so you have a working example on load.
Source height (px)
The source height used in the calculation, measured in px. Starts at 1080 px so you have a working example on load.
Target ratio
Pick the option that matches your situation — the maths changes per option. Choices: 16:9 — widescreen / YouTube, 9:16 — Shorts, Reels, TikTok, 1:1 — square feed, 4:5 — Instagram portrait, 3:2 — classic 35 mm, 4:3 — Micro Four Thirds / iPad, 2.39:1 — anamorphic cinema.
Scale to width (px)
The scale to width used in the calculation, measured in px. Starts at 1080 px so you have a working example on load.

Results

Height at your scaled width (px)
Returned as a decimal number and shown as the headline result. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
Crop-to-fill width (px)
Returned as a decimal number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
Crop-to-fill height (px)
Returned as a decimal number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
Frame area lost to crop
Returned as a percentage. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
Source ratio (decimal)
Returned as a plain value. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
If you letterbox instead
Returned as a plain value. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.

FAQ

Should I shoot vertical or crop from horizontal?

Crop from horizontal only if you framed for it with room on the sides. Cropping 16:9 to 9:16 discards about 68% of the frame, so composition and resolution both take a hit.

What is the safest single ratio for social?

4:5 vertical. It occupies more feed height than square, still crops cleanly to 1:1, and survives a 9:16 center-crop better than 16:9 does.

Accuracy and limitations

  • Estimates assume standard, average conditions — local rules, pricing, and materials vary.
  • Results are rounded for readability; add a buffer before ordering, booking, or committing.
  • Double-check anything with a real cost attached against a local quote.

Related tools

Print Size & Resolution Calculator

Largest quality print from your megapixels, and the DPI you'll get.

Video File Size Calculator

File size from bitrate and duration — or the bitrate to hit a size cap.

Cite this calculator

Writing about this topic? Grab a citation — every link helps keep these tools free.

APA
RevenueLab. (2026). Aspect Ratio Calculator. Retrieved from https://www.revenuelab.fyi/toolbox/aspect-ratio-frame
HTML
<p>Source: <a href="https://www.revenuelab.fyi/toolbox/aspect-ratio-frame" target="_blank" rel="noopener">Aspect Ratio Calculator — RevenueLab</a> (2026).</p>
Markdown
Source: [Aspect Ratio Calculator — RevenueLab](https://www.revenuelab.fyi/toolbox/aspect-ratio-frame) (2026).
Advertisement