Compress Image for Email

Need to compress images for email before attaching? Email wasn't designed for large attachments — the underlying IMAP/SMTP protocols date from the 1980s when 1 MB attachments were considered generous. Modern providers allow image attachments up to 25 MB (Gmail), 20 MB (Outlook, iCloud Mail), 25 MB (ProtonMail, Fastmail), but inline-embedded images should be much smaller (100-500 KB) for instant loading in recipient preview panes. Files above ~5 MB get rejected outright or trigger the dreaded 'use Google Drive instead' friction that kills engagement — recipients see the prompt and abandon. This email image compressor pre-compresses below 500 KB locally with adaptive quality calculation, producing JPEG files that attach directly to emails and load instantly in recipient preview panes.

• 1Gmail's 25 MB wall rejects anything larger — instead of allowing the upload, Gmail prompts 'use Google Drive instead' which adds click friction that kills engagement. Pre-compression avoids this entirely.
• 2Outlook's 20 MB and iCloud Mail's 20 MB limits are even tighter. Some corporate Exchange tenants cap at 10 MB. Pre-compressing to 500 KB covers all major providers safely.
• 3Inline-embedded images get watched 3-5x more than attached images, but only if they load instantly. Pre-compression ensures the instant loading that drives engagement.
• 4Local processing keeps personal and business Confidential images off cloud services. Critical for HIPAA-protected medical content, attorney-client privileged material, and family photos of minors.
• 5Adaptive quality: based on image content, the engine binary-searches JPEG quality to hit the target size precisely. A simple graphic might hit 500 KB at q90; a complex photo might need q70 — both stay under the limit.
• 6Pre-compressed JPEG files play inline in modern mail clients (Gmail web, Apple Mail, Outlook web, Fastmail) without requiring recipient download first.
• 7Marketing emails with inline images get significantly higher click-through rates than emails with attached files. Pre-compression makes inline embedding practical for any photo content.
• 8Spam filters sometimes flag emails with large attachments as suspicious. Pre-compressing images keeps total email size small, improving deliverability through Gmail, Outlook, and corporate filters.