Best duplicate file checker for quickly finding duplicates on Windows or Mac?

When you're using a duplicate file checker on Windows or Mac, there are a few common pitfalls you want to dodge to avoid headaches later on. Based on my own experiences and what I've seen happen, here’s what to watch out for:

• Sometimes, these tools can mistake different files as duplicates just because they have similar names or sizes. For example, two photos with the same name but different content. Always double-check the actual file contents before deleting anything. A good tip is to use a tool that shows preview images or file details so you don’t accidentally delete important stuff.
• Many beginner tools just compare filenames or file sizes, which isn’t reliable. Two files might look identical but actually have different data. Always opt for a tool that does byte-by-byte comparison or checksum verification to make sure the files are truly identical.
• Some duplicate checkers might flag system files or application files as duplicates, especially if they’re in similar folders. Deleting these can cause issues or break your programs. Be extra cautious and exclude system folders unless you know what you're doing.
• It’s tempting to just hit delete on all duplicates, but sometimes you’ll remove files you actually want to keep. Take your time, review each duplicate pair carefully, and maybe back up your data first. Trust me, it’s better to be safe than sorry.
• Some free duplicate file checker are buggy or overly aggressive, which can lead to unintended deletions or even malware. Stick to reputable, well-reviewed software, and maybe run a quick virus scan first.