Image Aspect Ratio Calculator
The Image Aspect Ratio Calculator determines the aspect ratio of any image from its pixel width and height. Calculate proportional resize dimensions, compare standard photo sizes, and ensure your images maintain the correct proportions across different platforms.
🕐 Recent Calculations
What is Image Aspect Ratio?
Image aspect ratio is the proportional relationship between an image's width and height measured in pixels. A 4000 × 3000 pixel image has a 4:3 aspect ratio. Knowing the aspect ratio is essential for cropping, resizing, and formatting images for web, print, and social media without distortion.
Standard image aspect ratios include 3:2 (DSLR cameras), 4:3 (smartphone cameras, micro four-thirds), 16:9 (screenshots, wallpapers), 1:1 (Instagram posts), and 5:4 (8×10 prints). The Image Aspect Ratio Calculator helps photographers and designers maintain consistency.
Formules et Équations utilisées
Ce calculateur s'appuie sur 5 équations fondamentales :
1 Image Aspect Ratio ▼
A 6000 × 4000 image: GCD = 2000, so ratio = 3 : 2. This is the standard DSLR sensor ratio.
2 Proportional Resize (New Height) ▼
Resizing a 4000×3000 image to 1200px wide: New Height = 1200 × (3000/4000) = 900 pixels.
3 Megapixel Calculation ▼
A 6000 × 4000 image = 24,000,000 pixels = 24 megapixels.
Comment utiliser ce calculateur
Pour utiliser ce Calculateur de Ratio, suivez ces 3 étapes :
Saisir les Valeurs
Saisissez les valeurs de ratio connues dans les champs. Laissez un champ vide — c'est la valeur manquante que le calculateur va chercher à résoudre.
Choisir le Mode
Sélectionnez le mode de ratio — Résoudre, Simplifier ou Mettre à l'échelle. Chaque mode applique des formules différentes à vos valeurs.
Obtenir les Résultats
Cliquez sur Calculer. L'écran de résultats affiche la réponse avec une barre de ratio interactive, un diagramme circulaire et le détail des calculs.
Exemples Pratiques et Solutions Étape par Étape
Voici 3 exemples de calculs résolus avec les étapes détaillées grâce à ce calculateur :
Saisie 1 Find aspect ratio of a 5184 × 3456 image
Saisie 2 Resize a 4032 × 3024 photo to 800px wide
Saisie 3 Calculate megapixels of 7680 × 4320
Foire Aux Questions
What aspect ratio do DSLR cameras use? ▼
Most DSLR cameras use a 3:2 aspect ratio, which matches the 35mm film format. Common resolutions include 6000×4000 (24MP), 6720×4480 (30MP), and 8256×5504 (45MP).
How do I find the aspect ratio of an image on my computer? ▼
Right-click the image → Properties → Details tab. Note the width and height in pixels. Divide both by their GCD to get the simplified aspect ratio. For example, 3840×2160 simplifies to 16:9.
What is the best image aspect ratio for Instagram? ▼
Instagram supports 1:1 (square, 1080×1080), 4:5 (portrait, 1080×1350), and 1.91:1 (landscape, 1080×566). The 4:5 portrait format takes up the most screen space in feeds.
Can I change an image's aspect ratio without cropping? ▼
Changing aspect ratio without cropping requires adding padding (letterboxing) or stretching the image. Stretching distorts the content. Adding colored bars preserves quality but changes the visual composition.
What resolution should I use for printing? ▼
For high-quality prints, use 300 DPI. An 8×10 inch print needs 2400×3000 pixels (4:5 ratio). A 16×20 inch poster needs 4800×6000 pixels.