Compress to a size
Pick the limit you have to meet, from 20 KB for an exam form to 25 MB for email, and get the best quality that fits. Free, and nothing is uploaded.
Name the limit, not the quality
A quality slider makes you guess, convert, check the size and guess again. Each page below starts from the number you actually have to meet and searches for the best quality under it, lowering the resolution only when it must.
Questions
How does it hit an exact size?
It encodes the file, measures it, and adjusts: first the quality, then the resolution if quality alone is not enough. Each attempt is a real encode, and the best one under the limit is kept.
What if my file is already under the limit?
It says so and leaves it alone. Re-encoding a file that already fits only makes it worse.
Is there a size limit on what I start with?
No fixed limit. Everything runs on your device, so the only ceiling is its memory.