Patent search tools help you conduct a patent search. Conducting a patent search helps ensure your invention hasn't already been patented by someone else. You can also get insight about what your competitors are developing.

Most commonly, an inventor conducts a patent search to find out if someone has already patented their invention. This involves sorting through existing patents, patent applications, and information about unpatented inventions. All of these preexisting inventions are called prior art.

Why Is a Patent Search Important?

A patent search tells you if pursuing a patent on your invention is worth it. If your search reveals a nearly identical invention has already been patented, your invention won't satisfy the novelty requirement for patentability. That means it isn't new or unique enough to qualify for a patent.

A patent search can also give you ideas about how to make your invention better. This can help your patent be more useful and less obvious, two other requirements for patentability.

A professional patent searcher will find things you are unlikely to discover if you do the search yourself. However, a professional search can be expensive. There are many tools available to help you perform your own search.

Patent Search Tools

Most tools listed here focus on U.S. patents and global patent databases. You can search for patents in other countries with regional databases. Two examples are the Canadian Patent Database or the Korean Intellectual Property Rights Information Service.

These databases are not always up to date. Use multiple tools to make sure your search is as thorough as possible.

Free Tools

Free search tools are a good way to get started on your patent search. The biggest downside is that many do not have a call center you can contact for help if you get stuck.

The United States Patent and Trademark Office Database

To learn to navigate this database, you can consult the Help Section the Patent Office's website. Here are some tips to get you started:

  • Create a long list of keywords that relate to your invention.
  • Using those keywords, go to the database's Index. This lists classifications and subclasses of patents are listed. Confirm where your invention belongs. It takes some time to become familiar with the classification system, but it is worth the effort.
  • Once you know the classifications and subclasses, use them as a starting point to sort through the available patent documents. The documents refer to other documents, which will help you expand your search.

Free Patents Online

Free Patents Online is easier and faster to use than the USPTO database. It provides quick access to PDF documents of patent applications, so it's easy to look at the illustrations on existing patents. The site has convenient hyperlinks to quickly compare different patents.

Google Patent Search

The biggest advantage of using Google to search for patents is that you'll get results very quickly. However, the search features are not as advanced as they are on other databases. Another drawback is that the Google database is missing some patents, especially recent ones. Still, you should use Google because it has information that stretches back further in time than what you'll find elsewhere.

This tool also has a Prior Art Finder tool that can help you learn about non-patented inventions that relate to yours.


Espacenet gives you access to more than 90 million patent documents from around the world. It even has a convenient translation feature that will help if you are looking at patents from outside the US.

Common Citation Document

Common Citation Document is a global search tool that lets you look at US, European, and Japanese patents. You can search according to patent family. You can use this in combination with other search tools.


SumoBrain lets you search for patents either by entering information into different fields or by conducting a Boolean search. A Boolean search lets you search for multiple keywords in the same document, even if those keywords don't occur together. You can create files that you can export, which makes it easy to compile your search results.

Patent Buddy

Patent Buddy doesn't let you search for patents. Rather, it is an analysis tool that gives you insight into patents. This can help you gain a deeper understanding of the patents you find during your search.


Octimine is a popular search tool that gives you analytics on your search results. It also offers information about prior art.

Patent Scope

Patent Scope is the database of the World Intellectual Property Organization (WIPO). You can search 30 million patent documents, including millions of PCT patents. PCT patents are otherwise known as international patents, and they are valid in multiple countries.

Patent Lens

Patent Lens has over 10 million documents that cover patents from several regions around the world, including the United States, Australia, and Europe.

Orbit is specifically for design patent searches. Most other sites focus on utility patents, which are the most common type of patent.

Thomson Innovation

Thomson Innovation offers search features and analytics. It also has a collaboration feature that is useful if you are working on a team rather than as an individual inventor.


Patbase is a database that has over 100 million documents that are related to patents. It is among the most popular paid patent search tools.

Derwent World Patent Index (DWPI)

The Derwent World Patent Index boasts that it is the world's most trusted patent information resource. It gives details about patents from around the world.


XLPAT does more than search for patents. It also helps you search non-patented items that might be related to your invention.

WIPS Global Advanced

WIPS Global Advanced is a Korean-based global patent search engine that lets you search by invention type, company, claims, or other criteria. It has smart analysis tools that may make your search easier.


Innography offers several advanced features that may make your patent search easier. It is geared toward professionals and lets you search according to keyword or concept. The filters give you a way to quickly narrow your search results. Innography's database has over 100 million patents documents from around the world.

MaxVal Patent Tools

MaxVal offers several patent-related tools that may speed up your search. One handy feature is the Patent Family Tree Generator, which lets you see information about a given patent and related patents. It also has a USPTO Widget that lets you search multiple patent databases by filling out just one form. You can even check if a patent has been involved in any court cases.


Petapator is a Chrome extension that organizes your patent search results. It includes analytics and a way to quickly export your search findings.


Patsnap is an extensive database that has patents from around the world, including the US, Europe, Japan, Korea, and China. The analytics features are useful for helping you organize your search. PatSnap lets you export documents with ease.

Patent Search Tips

  • Don't stick to basic keyword searches. Use the Advanced Search page of any database you use. Use the Specification field to find certain types of inventions.
  • Start your search using broad search terms. Then, narrow down your results.
  • Experiment with different keywords. The way you describe your invention might not be how similar inventions are described in patents.
  • Be patient when looking through search results. You need to determine which results are relevant, and there will be many that are not.
  • Keep track of anything you find. Put together a file, and clearly mark anything of interest.
  • After a preliminary search, hire a professional so you can be sure you didn't miss anything important.


Patent searching is a time-consuming process, especially if you've never done it before. Fortunately, many online tools can help you find the information you need. If you need help, you can post your questions or concern on UpCounsel's marketplace. Lawyers on UpCounsel come from law schools such as Harvard Law and Yale Law, with an average of 14 years of legal experience.

After you have conducted your preliminary search, hire a professional to help you with the rest of the patent application process.