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Resize image to 851x315
851x315 is widely used for legacy Facebook cover safe dimensions. Use this page to apply the exact dimensions instantly.
- Runs on your device
- 851x315
Drop images here
or browse · one image on Free
Supported: JPG, PNG, WEBP, GIF, BMP, AVIF.
Fill & crop keeps the shape and trims the overflow. Stretch distorts the image.
Lanczos and bicubic average many surrounding pixels, which keeps fine detail clean when shrinking. Nearest copies single pixels and suits pixel art.
Any good downscale softens the image slightly. This adds a little edge contrast back. Applied only when the image gets smaller.
On by default, so a size larger than the original is still honoured. Turn it off to never upscale — enlarging cannot add detail that was never captured.
Higher keeps more detail and produces a larger file.
Free resizes one image at a time.
Free exports up to 4096px on the longest side
Why 851x315 matters
851x315 is widely used for legacy Facebook cover safe dimensions. Use this page to apply the exact dimensions instantly.
- • Aspect ratio: 851:315
- • Best fit for: legacy Facebook cover safe dimensions
- • Orientation: landscape
- • Ratio family: custom
- • Tip: use WebP/JPEG for smaller files and PNG for transparency.
Preset logic and quality guidance
This page auto-applies exact dimensions from the URL preset. The tool uses high-quality scaling and keeps conversion on your device for privacy and speed.
- • Best for photos: WebP or JPEG for small file sizes and fast page loads.
- • Best for graphics: PNG when you need transparency or sharp UI edges.
- • If source is much smaller than target size, minor softness can appear after upscaling.
- • Lightweight assets for fast loading and compact placements.
Practical use-case depth
This 851x315 page is tuned for landscape layouts such as thumbnails, banners, and hero media. It is especially useful when you need exact outputs for legacy Facebook cover safe dimensions.
Exact-dimension export helps reduce platform-side recropping and prevents inconsistent rendering between desktop and mobile placements.
Social publishing intent
This size aligns with social placements where platform recropping is common. Using exact dimensions reduces quality loss from repeated platform-side resizing.
Preset-specific quality profile
The 851x315 target equals roughly 0.27 MP at a 851:315 ratio. This gives this preset a distinct balance between frame shape and detail density.
In practice, this behaves like a compact-density asset profile tuned for standard-web outputs and social publishing workflows.
Nearby size alternatives
Alternative aspect-ratio options
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