PDF Redactly vs Sejda
Sejda is a well-regarded online (and desktop) PDF toolkit with a redaction feature. Its free tier is usable but limited — at the time of writing, a small number of tasks per hour plus page and file-size caps — and the online version uploads your file, deleting it after a couple of hours.
PDF Redactly has no hourly limit on the free tier and never uploads the file. Here's the comparison.
Why people switch
Sejda's free tier limits tasks per hour and file size. PDF Redactly's free tier doesn't cap how much you redact.
Sejda uploads your file and deletes it later. PDF Redactly keeps it in your browser the entire time.
30+ categories are flagged for you, free, instead of manual selection.
Where Sejda wins: a broad, privacy-conscious toolkit with both online and desktop versions and a clean interface. If you want an all-purpose PDF suite and the free limits are fine for you, it's a good choice. For unlimited, never-uploaded redaction, PDF Redactly is the focused tool.
FAQ
Sejda's free tier limits the number of tasks per hour and caps file size and page count at the time of writing. PDF Redactly's free tier has no such caps.
Yes — the online version uploads and deletes the file after a couple of hours. PDF Redactly never uploads it; redaction runs in your browser.