What causes "Why Is Sync.com So Slow? Upload and Download Speed Fixes"?

Client-side encryption adds CPU work on your computer No block-level sync: edited files upload in full Large initial upload of hundreds of GB Other heavy apps competing for CPU, RAM and disk Using the web panel for large transfers VPN, firewall or network throttling

How do I fix "Why Is Sync.com So Slow? Upload and Download Speed Fixes"?

1. Close heavy apps and restart: Close video editors, games and other heavy programs while syncing Restart the computer and let Sync run on its own for a while 2. Use the desktop app for big transfers: Copy large files into the Sync folder rather than uploading through the browser Sync recommends the desktop app because it handles large data sets more efficiently 3. Upload in batches: Move a large library into the Sync folder in chunks of a few folders at a time Let each batch finish before adding the next 4. Keep frequently edited big files out of Sync: Avoid syncing files you save constantly (VM images, PST files, video projects) Sync the final export instead, since every save re-uploads the whole file 5. Check your network: Pause the VPN and test speed again Try a wired connection or a different network Check status.sync.com for an ongoing incident

// troubleshooting guide · sync.com

Why Is Sync.com So Slow? Upload and Download Speed Fixes

Status: Ongoing
platforms:: Windows, macOS, Web
updated:: November 15, 2026
reports:: 5
Method: how we research

RUNBOOK · sync-com/slow5 FIXES

// quick answer

Sync.com is slower than Dropbox because files are encrypted on your device and there's no block-level sync, so whole files re-upload on every change. Close resource-heavy apps, keep the app updated, use the desktop app instead of the browser for big transfers, and give large first uploads time.

Most likely fix: Close heavy apps and restart

How to fix it

// try these in order, the most common fix is first

FIX 1Close heavy apps and restart
1. 01Close video editors, games and other heavy programs while syncing
2. 02Restart the computer and let Sync run on its own for a while
Did this fix it?
FIX 2Use the desktop app for big transfers
1. 01Copy large files into the Sync folder rather than uploading through the browser
2. 02Sync recommends the desktop app because it handles large data sets more efficiently
Did this fix it?
FIX 3Upload in batches
1. 01Move a large library into the Sync folder in chunks of a few folders at a time
2. 02Let each batch finish before adding the next
Did this fix it?
FIX 4Keep frequently edited big files out of Sync
1. 01Avoid syncing files you save constantly (VM images, PST files, video projects)
2. 02Sync the final export instead, since every save re-uploads the whole file
Did this fix it?
FIX 5Check your network
1. 01Pause the VPN and test speed again
2. 02Try a wired connection or a different network
3. 03Check status.sync.com for an ongoing incident
Did this fix it?

Symptoms

Uploads and downloads take far longer than your connection speed suggests, even small files take minutes, the first upload of a large library runs for days, or the app pauses during transfers.