A friend asked me to recommend a browser add-on that would allow her to see generic results when she did a Google search. I convinced her to eschew extensions in favor of the manual approach to search depersonalization.
Google's support site explains how the company uses what it knows about you to personalize your search results. The site also describes how to restrict who sees your personal results, limit whose personal results you see, and customize the feature in other ways.
The most-obvious way to depersonalize searches --at least partially -- is to use your browser's anonymous mode. In Google Chrome, click the wrench icon in the top-right corner and choose New Incognito Window (or press Ctrl-Shift-N in Windows or Command-Shift-N on a Mac). In Firefox, click Tools > Start Private Browsing (or press Ctrl-Shift-P in Windows or Command-Shift-P on a Mac). In Internet Explorer, click the gear icon in the top-right corner and choose Safety > InPrivate Browsing (or press Ctrl-Shift-P). Safari's Private Browsing option is on the program's main drop-down menu.
Note that even when browsing anonymously while signed out Google may personalize your searches to a limited extent because the service's cookies remain active. Cookie-management options are described below.
Toggle personalized search results on and off with one click
If you're signed into a Google account when you search, click the globe icon in the top-right corner of the browser window to view the depersonalized version of the search results. Click the person icon to revert to the results filtered by Google's knowledge of your Web history, your current location, the device you're using, and other data specific to you.
After comparing the personalized and generic results of 25 searches of various types, I found only a handful of the top-10 results changed for most searches, and for several search terms there was no change in the top-10 results with and without personalization.
Likewise, the top result returned in my test searches changed for only 3 of the 25 terms I entered when disabling personalization. As expected, the biggest difference between personal and generic results occurred when I entered words and phrases I had searched for previously.
Turn off personal results in Google's Search Settings
Whenever you open a new Google search window while signed into an account, the default is to personalize your searches even if you selected the "Hide personal results" icon in your most recent search session.
To disable personal search results once and for all, click the gear icon in the top-right corner of the window, choose Search Settings, scroll to Personal Results near the middle of the page, and choose "Do not use personal results."
Note that disabling personal results doesn't prevent your searches from being recorded in your Web history. To pause the Web history feature, click the gear icon, choose Web History, sign into the account (if necessary), and click the Pause button (you can also remove all or part of your Web history). Repeat the steps and click Resume to reactivate the feature.
For information on how to customize your Web history, see my post from July 2009 entitled "Make use of what Google knows about you."
The one-fell-swoop approach: delete your cookies
Perhaps the simplest way to ensure you're getting generic search results is to delete all the cookies from your browser. Google's support site provides instructions for clearing the cache and cookies from Chrome, Firefox, Internet Explorer, Safari, and Opera.
Of course, Google and nearly every site you visit deposits a fresh cookie in your browser as soon as you arrive. Blocking all cookies -- first-party and third-party alike -- renders the Web nearly useless. An alternative is to set your browser to delete all cookies each time you close the program.
To set Chrome to delete cookies on exit, click the wrench icon in the top-right corner of the window, choose Settings > Under the Hood > Content Settings, and select "Clear cookies and other site and plug-in data when I quit my browser."
In Firefox, click Tools > Options > Privacy (Windows) or Firefox > Preferences > Privacy (Mac) and choose "Use custom settings for history" in the History drop-down menu. (If the main menu isn't visible, press Alt.) Check "Clear history when Firefox closes" and click the Settings button to the right. In the resulting dialog box, check Cookies and any other category of data you want to erase when you close the browser.
To set IE to delete your history when it closes, click Tools > Internet Options > General and check "Delete browsing history on exit." (Press the Alt key to bring IE's main menu into view.)
Opt out of the Google cookie
For those who prefer not to toss their cookies, as it were, whenever they close their browser, Google lets you opt out of the company's tracking cookie. First, sign out of your Google account. Then click the gear icon in the top-right corner and choose Web History. Select "Disable customizations based on search history."
This setting is controlled by a Google cookie, so if your browser is set to delete cookies on exit, you'll have to add this cookie to your list of exceptions. You can access your exception list via the steps described above for clearing your cookies.
For example, in Chrome, click Manage Exceptions in the Content Settings dialog, enter the "Hostname Pattern," and choose Allow in the drop-down menu on the right. Type "[*.google.com]" (without the quote marks) under Hostname Pattern to apply the setting to all Google cookies.
The Google support site offers more information on using the browser's cookie-management options.
Create a depersonalized version of Google search
Chrome lets you roll your own version of Google search that disables personalization and can be set as the browser's default search service. Click the wrench icon in the top-right corner and choose Settings (or on a Mac, press Command-,). Select Basics in the left pane and click Manage Search Engines in the Search section.
At the bottom of the list of "Other search engines" is a blank entry for adding a new search engine. Enter a name such as "Depersonalized" in the first text box and add a URL such as "www.google.com" in the keyword box. Type the following line in the text box labelled "URL with %s in place of query":
Click Make Default in the new entry to have all your search results come up generic.
To revert to Google's personalized version, just return to the Basics settings and choose Google or another search option on the drop-down menu.