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Most email providers cap attachments at 10–25MB, but large images slow down inboxes and often get blocked by corporate mail filters. Compress your photos to under 1MB before attaching — all in your browser, no server involved.
PNG, JPG, GIF, WebP, HEIC up to 50MB per file
Choose filesGmail caps attachments at 25MB, Outlook and Microsoft 365 at 20MB, and many corporate mail servers are stricter still, often 10MB. These limits apply to the encoded message rather than the raw file: email attachments are encoded in base64, which inflates them by roughly 33%. A 20MB file therefore arrives at the server as about 27MB and bounces against a 25MB cap.
Because of that overhead, the real usable budget is about three quarters of the stated limit. Keeping a set of photos under 10MB total is a safe rule that works with essentially every mail provider and corporate filter.
For photos meant to be looked at on a screen, 1600px at 80% quality is generous — that usually lands between 200KB and 400KB per image, so you can attach twenty of them and still stay under 10MB. If the recipient needs to print, keep 300 DPI at the intended print size, which means around 2500px for a standard A4 page.
One habit worth adopting: send several moderately compressed photos rather than one enormous one. Large attachments are the most common reason emails are silently quarantined by corporate spam filters, and the sender is rarely told.
Aim for under 1MB per image. At 70% JPEG quality and 1280px max dimension, most photos land between 100–400KB — clear enough to view on screen, small enough not to clog inboxes.
Corporate mail servers, spam filters and mobile email clients often block or strip attachments over 1–5MB. Compressing before sending prevents rejected messages and storage quota issues.
Yes. Drag all your photos at once and download them as a ZIP — then attach the individual compressed files to your email.
JPEG for photos — it achieves the smallest sizes. Only use PNG if the image has transparency or is a screenshot/diagram where sharp edges matter more than file size.