iLovePDF processes your file on their servers and caps free usage per tool — merge tops out at 25 files, compress at 2 operations, before it asks you to sign up or upgrade. iampdf runs the same category of tools locally in your browser instead, so there's no server-side cap to hit and no file that leaves your device.
Compared against iLovePDF’s own pricing page, last checked August 2026. Their plans can change after that date — verify current details on their site before relying on this for a purchase decision.