Toollyst, TrackFollows, FollowCop and CheckMate checked on nine criteria: login requirements, file storage, processing location, username-change handling and more. Disclosed up front: our own tool is one of the four.
Search for "Instagram unfollowers" and you get dozens of tools. Try one and you find that some ask for your username and password while others only want a file. They all look like the same "unfollower check", but they handle your data in fundamentally different ways, and that difference goes straight to account safety and privacy. So I picked four representative tools that I could either try myself or verify from public documentation, and judged them on the nine questions users actually ask.
One thing first. As disclosed above, this comparison includes our own service, CheckMate. Self-comparisons slide into advertising easily, so I set three rules to avoid that trap. First, every cell is filled only from verifiable sources: public pages, official FAQs, app store listings. Second, anything unverified stays "no public information" instead of a guess. Third, at least one CheckMate weakness is stated explicitly (see below).
The method and its limits are also stated openly. All checks were carried out on 11 June 2026. At that time the main pages of Toollyst and TrackFollows blocked automated access (rate limiting), so I could not open them directly; instead I relied on their public usage guides, search-indexed page content and official app store listings. For account-linked features that require a username and password, I did not sign up or log in, for security reasons, and evaluated the behaviour described in public documentation and FAQs. Because of these limits, a few cells inevitably remain "no public information".
The nine criteria are: (1) whether a login or password is required, (2) whether the file is stored on a server, (3) where processing happens (server or browser), (4) whether limited date-range data is explained, (5) how username changes are handled and disclosed, (6) price and ads, (7) analysis method (file upload or account link), (8) whether a privacy policy exists and how specific it is, (9) PC support. What each criterion means and why it matters is explained below the table.
The table reflects what was verified on 11 June 2026. Only the CheckMate column is tinted light blue, so that our own entries sit under the same yardstick in plain view rather than being hidden.
| Criterion | Toollyst | TrackFollows | FollowCop | CheckMate (ours) |
|---|---|---|---|---|
| 1. Login / password | Not required (file upload) | Not required (states "no login") | Required (account login) | Not required (file upload) |
| 2. File stored on server | No public information | No public information (states "on-device") | No public information | Not stored (processed in the browser, never sent to a server) |
| 3. Processing location | Browser (upload-based) | On device / browser | App and server (account-linked) | Browser |
| 4. Explains limited-range data | No public information | Has a related notice (covers deactivated and deleted accounts) | No public information | Explained in the blog and in the tool |
| 5. Username-change handling and disclosure | No dedicated handling or disclosure found | No dedicated handling or disclosure found | No dedicated handling or disclosure found | Shown separately as an estimate, with ambiguous cases split out |
| 6. Price and ads | No public information | Listed as free | Free (ads) + premium | Free (no ads shown at present) |
| 7. Analysis method | File upload | File upload | Account link | File upload |
| 8. Privacy policy | No public information (could not be checked directly) | No public information (could not be checked directly) | FAQ exists, but no policy document was found | Yes (dedicated page) |
| 9. PC support | PC and mobile web | Web + app | Mobile app only | PC and mobile web |
The sharpest fork in the table is rows 1 and 7. Toollyst, TrackFollows and CheckMate are upload-based: you provide the official export file, so no password is needed. FollowCop is account-linked: it connects to your account directly, so it needs your login. That single difference shapes most of the other rows. Section 4 explains why, with the terms of use as the reference.
Each tool gets its strengths first; limitations are noted only where facts support them. None of these tools is dismissed outright. Which one fits best depends on your purpose and situation.
Strengths. An upload-based tool aimed squarely at Korean users. Its public guide lays out a clear flow: in Instagram, tick only "Followers and following", download the data as all-time JSON, upload the ZIP, press analyse, and it lists the accounts you follow that do not follow you back. It never asks for your login details, so there is no password-leak risk, which is its biggest advantage. It works in both PC and mobile browsers.
Limitations (fact-based). Because the main page blocked automated access at the time of checking, I could not verify directly whether a privacy policy exists, how specific it is, or whether uploaded files are stored on a server. The public guide also contains nothing about handling or disclosing username changes. That is not a finding that it "does not handle them"; it means no evidence was found (hence "no public information" in the table).
Strengths. An upload-based tool whose public description leads with "no login, 100% free, on-device analysis". It supports both Korean and English and offers a separate mobile app. What stood out is that it warns in advance that, because of changes to Instagram's data policy, deactivated and deleted accounts can remain in the following list and make results look inaccurate. I rated that positively as a genuine attempt to pre-empt a confusion users run into all the time.
Limitations (fact-based). As with Toollyst, direct access to the main page was blocked, so the privacy policy document itself could not be verified. "On-device analysis" suggests browser processing, but without seeing a policy document that backs it up, row 2 (server storage) stays "no public information". No feature that estimates and separates username changes was found either.
Strengths. A mobile app on Google Play whose strength is that management actions, such as unfollowing several accounts at once, can be done right inside the app. You can start for free (ad-supported), and it offers extras such as fake-follower and mutual filters. For anyone who wants to go beyond "checking" and clean up in a single flow, that is convenient.
Limitations (fact-based). The most important difference is that it is account-linked: it logs in to your account directly. The official FAQ is written on the premise that you "log in to your account", and it says that if you have two-factor authentication (2FA) enabled you must temporarily turn it off. In other words, you disable a security safeguard for a while and hand your credentials to the app. It is also mobile-only, so it cannot be used on a PC, and the specifics of its data-safety section and privacy policy could not be conclusively verified at the time of checking. According to the app listing, it is not affiliated with Instagram. Why a login requirement is risky is covered in the next section, with the terms of use as the reference.
Strengths. Upload-based, accepting only the official export ZIP or JSON, so no login or password is needed. The uploaded file is processed entirely inside the browser. The contents of the uploaded file, follower list included, are never sent to a server and never stored. The biggest difference from the other tools is that it shows possible username changes separately as an estimate, and moves cases where several changes overlap at the same time, and cannot be pinned down, into an "ambiguous" group. The reasoning and its limits, formulas included, are laid out in the username-change tracking study. It works on PC and mobile web and has a dedicated privacy policy page.
Back to row 1. Upload-based tools (Toollyst, TrackFollows, CheckMate) never ask for a password; the account-linked tool (FollowCop) requires a login. There is a reason this is a matter of safety, not mere convenience.
Instagram's Terms of Use prohibit accessing accounts or collecting data by unauthorised automated means. Handing your username and password to a third-party app that logs in on your behalf and scrapes your followers is very likely to fall under that prohibition on automated collection. In practice such tools can be detected as abnormal access and lead to login blocks or account restrictions. FollowCop telling you to turn off two-factor authentication is a consequence of the same thing: the safeguard blocks automated logins. Put differently, you deliberately switch off the device that protects your account and entrust your credentials to an outside party.
There is a security angle too. Once you type in a password, you have no control over where or how those credentials are stored and transmitted. Upload-based tools, on the other hand, handle only the export file Instagram provides officially, so a password never enters the picture. What fake followers and dubious third-party tools can do to an account is covered in more depth in the fake followers and third-party tool risks post, which is worth reading before choosing a tool.
The answer is not "which is best" but "which fits your situation". Three common scenarios:
The most common case. Here an upload-based tool is all you need. No password means it is safe, and if you only check once you do not need alerts. Toollyst, TrackFollows and CheckMate all fit. If you prefer a comfortable view on a PC, a web tool beats the mobile-only FollowCop.
If the question is "who dropped off since last month", you must compare data from two points in time. The key is keeping an earlier export and comparing it with the latest one. CheckMate's two-snapshot comparison (unfollow tracker) was built for exactly this: upload two ZIPs and it separates unfollowers from new followers. As noted above, there are no real-time alerts, so if instant push notifications are essential, an account-linked app (FollowCop, for example) with its alert feature may be the alternative. It is a trade-off between convenience and safety.
A common misunderstanding among Korean users, who change usernames often. A simple list-comparison tool shows a renamed account twice, as "unfollowed" plus "new". To reduce that, you need a tool that estimates renames and separates them, and of the four tools checked, only CheckMate does this explicitly. But it is an estimate, not a verdict, and several changes at the same time end up in the ambiguous group. Where that line is drawn is documented in the username-change tracking study.
It depends on how the tool works. Tools that take the official data export file (upload-based tools) send no automated requests to Instagram's servers, so the suspension risk is effectively nil. Tools that ask for your username and password and log in on your behalf (account-linked tools) may fall foul of the terms that prohibit automated collection, and handing your password to a third party adds a security risk on top.
The core analysis (mutuals and unfollower lists) is free almost everywhere. Paid features are mostly attached to automated tracking over time and push notifications. Upload-based tools cannot keep pulling data in the background by design, so real-time alerts are impossible and an ad-supported free model is the norm. If you need alerts, an account-linked app has the edge, but you pay for it by handing over your login and permissions.
Everything was checked on 11 June 2026 against each service's public pages, official FAQ and app store listing. Features and policies can change afterwards, so please read each service's latest documentation and privacy policy before using it.
zipProcessor.ts, in-browser processing, no server upload) and direct verification by the operator, June 2026How renames are separated as estimates, and the limits, formulas included
The risks of fake followers and third-party toolsWhat tools that demand a login can do to your account
Two-snapshot comparison: the unfollow trackerUpload an older and a newer export to see changes over a period