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Thumbnail & Cover Image Size Calculator
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This tool references the standard thumbnail and cover image dimensions for YouTube, Instagram, TikTok, Twitter/X, Facebook, LinkedIn, and podcast cover art — the exact pixel sizes platforms recommend so your image isn't cropped, stretched, or compressed unexpectedly. Optionally enter your own image's width and height to see its aspect ratio and find the closest matching standard format. It's a quick reference before exporting or designing thumbnails and cover art. Everything runs locally in your browser. Scroll down to see the size reference.
Features
- Reference sizes for major platforms in one place
- Finds the closest standard format for your own image dimensions
- Shows aspect ratio comparison
- Always up to date with common platform conventions
Why use this thumbnail & cover image size calculator?
- Avoids re-uploading a poorly-cropped thumbnail
- One reference instead of searching multiple platform help pages
- Fully private — nothing uploaded
- Free with unlimited use
Frequently asked questions
What size should a YouTube thumbnail be?
1280 × 720 pixels (16:9 ratio) is YouTube's recommended thumbnail size, displayed at various smaller sizes across the platform but uploaded at this resolution for best quality.
What size should an Instagram post be?
1080 × 1080 pixels for a square post is a safe standard size; Stories and Reels use a taller 1080 × 1920 (9:16) format instead.
Do these sizes change over time?
Platforms occasionally adjust their recommended sizes, so it's worth double-checking a platform's current official help documentation for pixel-perfect requirements on major campaigns.
What happens if my image doesn't match the exact size?
Most platforms will crop or scale your image to fit, which can cut off important content — designing at or near the exact recommended size and aspect ratio avoids unexpected cropping.
Why does the tool suggest a 'closest format' for my image?
It compares your image's aspect ratio to each platform preset's ratio to suggest which one it's already closest to, helping you decide whether to keep, crop, or resize it.