Proxies vs Google Topics API: How to Protect Privacy and Ad Accounts in 2026

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Google has definitively abandoned FLoC but launched the Topics API — a new technology for tracking interests directly within the Chrome browser. For arbitrageurs, SMM specialists, and marketers, this means new risks: advertising platform algorithms receive additional signals about the user that can link accounts and provoke bans. In this guide, we explore how the Topics API works, why it is dangerous for multi-accounting, and how proxies combined with anti-detect browsers help maintain privacy in 2026.

What is FLoC and Topics API: what is the difference

To understand why protection is needed at all, it is essential to grasp what Google was trying to achieve with FLoC and what ultimately resulted in the Topics API. These are not just technical terms — they are mechanisms that directly affect how advertising platforms perceive your accounts and online behavior.

FLoC (Federated Learning of Cohorts) — was Google's first attempt to replace third-party cookies. The idea was that the Chrome browser would analyze the user's browsing history and assign them to one of thousands of "cohorts" — groups of people with similar interests. Advertisers would receive not a specific user ID, but a cohort number. It seemed more private. However, in practice, FLoC created a unique "fingerprint" of the browser, which could identify users even more accurately than cookies. In 2022, Google shut down the project after a wave of criticism from regulators, browser competitors, and human rights advocates.

Topics API — is the successor to FLoC, launched in Chrome starting with version 115 and actively developing in 2025–2026. The principle of operation has changed: now the browser does not assign you to a cohort but determines 5 "topics" from your browsing history over the last 3 weeks. For example: "Sports," "Finance," "Technology." When you visit a site with advertising, that site can request one of your topics from the browser — and receive it for targeting.

Key difference between FLoC vs Topics API:

• FLoC: one cohort ID = unique fingerprint, easy to identify a specific user
• Topics API: 5 broad topics = less uniqueness, but still transmits browsing behavior data to advertising systems
• Common: both mechanisms operate within Chrome and do not require third-party cookies — disabling them is more challenging

For the average user, the difference is minimal. But for an arbitrageur managing 20–50 advertising accounts on Facebook Ads or TikTok Ads, the Topics API is an additional signal that can link accounts together or reveal unusual behavior to the anti-fraud algorithm.

How Topics API tracks you in 2026

In 2026, the Topics API is built into Chrome by default and active for most users. It is essential to understand the mechanics of its operation to realize where the threat to multi-accounting arises.

Step 1: Collecting history. Chrome analyzes which sites you visit and matches them with a taxonomy of several hundred thematic categories (version 2 of the taxonomy includes over 470 topics). This occurs locally on your device — data is not sent directly to Google.

Step 2: Forming the top 5 topics over 3 weeks. Every week, Chrome determines the 5 most relevant topics based on history. The topics are stored in the browser and updated weekly. One of the 5 topics is randomly selected — this is an embedded "protection" against precise identification.

Step 3: Transmitting the topic to the advertiser. When you visit a site that participates in the Topics API (which includes most sites with Google ads), the JavaScript code on the page makes a request to the browser: "Give me one of this user's topics." The browser returns a topic — but only one that was formed on sites where this advertiser was already present. This is called an "observer" (caller).

Why is this important for multi-accounting? Suppose you are working with several Facebook Ads accounts. All of them are opened in the same browser — Chrome. Even if each account has different cookies and different proxies, the Topics API transmits the same topics for all sessions because topics are formed at the browser profile level, not on a separate tab. The Facebook anti-fraud algorithm may detect that several accounts with different IPs have the same "thematic profile" — and this is a signal for verification.

Why Topics API is dangerous for arbitrageurs and SMM

Let's analyze specific scenarios where the Topics API creates real risks for professionals working with multiple accounts.

Scenario 1: Traffic arbitrage through Facebook Ads

An arbitrageur manages 10–30 Facebook Ads accounts. Each account is a separate profile in an anti-detect browser like Dolphin Anty or AdsPower with unique cookies and proxies. However, if all profiles are opened through regular Chrome or if the anti-detect browser does not block the Topics API, all accounts receive a similar thematic profile formed based on actual browsing history. Facebook sees: different IPs, different cookies, but the same Topics API topics → suspicion of linked accounts → chain ban.

Scenario 2: SMM agency with 30+ Instagram accounts

An SMM specialist manages client accounts on Instagram. Most actions are performed through the browser or mobile app. If the web version of Instagram is used in Chrome, the Topics API is active. During mass actions (likes, follows, posts), Instagram receives not only the IP and User-Agent but also the thematic signal — and all accounts managed from one device have a similar profile.

Scenario 3: Marketer testing ads from different regions

A marketer wants to see how competitors' ads appear in Google Ads for users from Moscow, Berlin, and New York. They change proxies but remain in one Chrome browser. The Topics API transmits the same thematic profile for all three sessions — and Google understands that this is the same user checking ads from different locations. The result: incorrect data about what the real audience sees.

Audience	Risk from Topics API	Consequence
Arbitrageurs (Facebook Ads)	Linking accounts by thematic profile	Chain ban, loss of accounts
SMM (Instagram, TikTok)	Same profile for different clients' accounts	Blocking for mass actions
Marketers (geo-tests)	Identification as one user	Incorrect data, account exposure
Sellers (scraping Wildberries, Ozon)	Repeated thematic signal during scraping	Accelerated ban of the scraper

How proxies protect against tracking through Topics API

It is important to clarify right away: a proxy by itself does not block the Topics API. This is a browser technology, and it operates at the Chrome level, not at the network connection level. A proxy changes your IP address but does not disable JavaScript requests within the browser.

Nevertheless, proxies play a key role in comprehensive protection — and here’s why.

Proxies isolate the network layer

Even if the Topics API transmits a thematic signal, without a unique IP, this signal is not tied to a specific geographical point. If each profile in the anti-detect browser has its own proxy with a unique IP, anti-fraud systems cannot link accounts based on network criteria. Proxies eliminate the most obvious signal — matching IP addresses.

Proxies create a plausible geo-context

Residential proxies provide IP addresses of real home users from specific cities and countries. When the Topics API transmits a topic "Finance" for an account with a residential IP from Moscow — it looks like an ordinary Moscow user interested in finance. The algorithm does not see a contradiction. However, if a data center proxy with an IP from AWS or Hetzner is used, the match "corporate IP + thematic profile" raises suspicions.

Proxy rotation resets accumulated context

The Topics API forms a profile over 3 weeks. If proxies are regularly changed and used in conjunction with isolated profiles in an anti-detect browser, each new profile begins its "life" with a clean slate — without accumulated topic history. This is especially important when farming new Facebook Ads accounts or working with TikTok Ads.

For tasks requiring maximum profile isolation, arbitrageurs often choose mobile proxies — they operate through real SIM cards from mobile operators and have the highest level of trust from Facebook and TikTok algorithms because they mimic the behavior of an ordinary mobile user.

Setting up an anti-detect browser + proxies against Topics API

Full protection from the Topics API requires proper configuration of the anti-detect browser. Let's look at how this is done in popular tools: Dolphin Anty, AdsPower, and GoLogin.

Step 1: Block Topics API in browser profile settings

Most modern anti-detect browsers (Dolphin Anty, Multilogin, Octo Browser, AdsPower) in 2025–2026 already have built-in settings to manage the Privacy Sandbox API, which includes the Topics API.

• Dolphin Anty: Open profile → "Browser" tab → "Privacy Sandbox" section → toggle Topics API to "Disabled." This blocks JavaScript requests document.browsingTopics() on all sites.
• AdsPower: Profile settings → "Advanced options" → "Chromium Flags" → find the flag privacy-sandbox-ads-apis → set the value to "Disabled."
• GoLogin: Edit profile → "Browser" tab → "Privacy Sandbox" → disable all switches related to Topics, Attribution Reporting, and Protected Audience API.
• Multilogin: Starting from version 6.x, the Topics API is disabled by default in Mimic and Stealthfox profiles — no additional settings are required.

Step 2: Assign a unique proxy to each profile

After disabling the Topics API in the browser, ensure that each profile uses a unique proxy. Here’s how to do it in Dolphin Anty:

1. Open Dolphin Anty → click "Create profile" or open an existing one
2. Go to the "Proxy" tab
3. Select the protocol type: SOCKS5 (recommended for residential and mobile proxies) or HTTP/HTTPS
4. Enter proxy details: host, port, username, password
5. Click "Check proxy" — wait for confirmation that the IP matches the desired region
6. Save the profile

Step 3: Synchronize geo-parameters of the profile with the proxy

This is a critically important step that beginners often overlook. If the proxy is from Berlin, all geo-parameters of the profile must correspond to Berlin:

• Time zone: set to Europe/Berlin
• Browser language: de-DE or en-US (depending on the account)
• Geolocation: enable automatic detection by the proxy IP
• Keyboard layout: corresponding to the country

If the Topics API is not completely blocked for some reason, the topics it transmits should make sense for a user from that region. A mismatch between geo-parameters and the thematic profile is an additional signal for anti-fraud.

Step 4: Warm up the profile with appropriate topics

When creating a new profile for farming Facebook Ads or TikTok Ads accounts, it is important to "warm up" the browser profile — visit several thematic websites that correspond to the account's legend. If the account is positioned as "an ordinary user from Moscow," visit several news sites, online stores, and sports portals. This forms an organic thematic profile that the Topics API will transmit to advertising systems.

Which type of proxy to choose for privacy protection

Not all proxies are equally effective in the context of protection against the Topics API and ensuring privacy during multi-accounting. Let's break down three main types.

Proxy Type	Trust Level	Suitable for	Not suitable for
Residential	High	Facebook Ads, Instagram, TikTok, Google Ads	High-speed scraping
Mobile	Maximum	Farming Facebook, TikTok Ads, accounts with a high risk of bans	Tasks requiring stable IP
Data Center	Low–Medium	Scraping Wildberries, Ozon, price monitoring	Advertising accounts, social networks

Residential proxies: optimal choice for most tasks

Residential proxies use IP addresses of real home users. When the Topics API transmits a thematic signal from such an IP, the advertising system sees an "ordinary user" — without flags of a corporate network or data center. This creates the most organic picture for anti-fraud algorithms.

Residential proxies are especially effective when working with Google Ads — Google is the developer of the Topics API, and its algorithms are most sensitive to mismatches between the type of IP and the thematic profile. A residential IP from the desired region + disabled Topics API in the anti-detect browser = minimal risk of identification.

Mobile proxies: for high-risk tasks

Mobile proxies operate through real mobile devices with SIM cards. Their feature is dynamically changing IPs (each time reconnecting to the network, the operator issues a new IP). This means that even if the Topics API has transmitted some signal, the next session from this proxy will have a different IP — and linking them is extremely difficult.

Arbitrageurs working with Facebook Ads and TikTok Ads in 2026 use mobile proxies for their most valuable accounts — those with large budgets. The cost is higher than residential proxies, but the level of protection is maximum.

Data center proxies: for scraping, not for accounts

Data center proxies are fast and cheap but are easily identified as "non-human" traffic. For tasks where the Topics API does not play a role (scraping prices on Wildberries, monitoring Avito, collecting data from open sources), they are excellent. But for advertising accounts and social networks — the risk is too high.

Checklist: complete protection from Google Topics API in 2026

Let's bring everything together. Here’s a step-by-step checklist for arbitrageurs, SMM specialists, and marketers who want to protect their accounts and privacy from the Google Topics API.

How to check if the Topics API is blocked

After setting up the anti-detect browser, be sure to check the result. Here’s how to do it without technical knowledge:

1. Launch the required profile in the anti-detect browser
2. Go to the site privacysandbox.com/intl/en_us/articles/topics/ — the official demo page for Google Topics API
3. If the Topics API is blocked, you will see the message "Topics API is not available" or an empty list of topics
4. Additionally: open the developer console (F12) → Console tab → enter document.browsingTopics() → if it returns an error or an empty array, the API is blocked

What to do if the anti-detect browser does not support blocking the Topics API

If you are using an outdated version of the anti-detect browser or a budget tool without support for Privacy Sandbox settings, there are workarounds:

• uBlock Origin extension: add a blocking rule for requests to the Topics API in the filters. Works in most Chromium-based anti-detect browsers.
• Chrome launch flags: when launching the browser, add the flag --disable-features=BrowsingTopics — this completely disables the Topics API at the engine level.
• Update the anti-detect browser: Dolphin Anty, AdsPower, and GoLogin are actively updating in 2025–2026 specifically regarding Privacy Sandbox protection. Make sure you are using the latest version.

Conclusion

Google Topics API is not just another advertising technology. For arbitrageurs, SMM specialists, and marketers working with multiple accounts, it represents a new vector of risk: an additional signal that can link accounts or reveal unusual behavior to the anti-fraud algorithm. In 2026, ignoring this threat means risking the loss of accounts and advertising budgets.

The good news: protection exists and does not require deep technical knowledge. The combination of "anti-detect browser with disabled Topics API + unique proxy for each profile + synchronized geo-parameters" covers most risks. The main thing is not to use one proxy for multiple accounts and to regularly update tools.

If you work with advertising accounts in Facebook Ads, TikTok Ads, or Google Ads and want to minimize the risk of bans, we recommend starting with residential proxies — they provide a high level of trust from advertising platforms and organically fit with the thematic profile that the Topics API creates. For the most valuable accounts with large budgets, consider mobile proxies — maximum protection and minimal risk of account linking.