If you want to resize one of your photos or document images (to make it smaller or larger), use a photo or image editor before uploading to Memories. You can also download a photo or document image from Memories, resize it, then upload it again.
You cannot resize documents if they are in PDF format.
Tip: For best results, the higher the pixel count and the larger the file size, the sharper the final image.
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Can I download the memories (photos, stories, documents, and audio files) about my ancestors?
How do I upload memories to FamilySearch?