You want to recruit an author for your blog but you want to be sure that the content you come up with will be unique and not copied entirely or plagiarized, you also want to check that no one has copied your content…

Even the blogger the most qualified absolutely cannot be aware of all the content that is already online in a specific niche. When writing about a particular subject, it is very easy to use phrases that are similar to those used on other sites.

If similar issues are being discussed in the blogosphere, it is not impossible that some similar content will appear, even inadvertently, if the work has been done by the blogger personally and not by copying and pasting from someone else's site.

For this reason, running a plagiarism check should be part of your standard of checks and balances before accepting work from a blogger. These five online plagiarism checking services can help you weed out any duplicate content.

1. Copyscape
Copyscape has the advantage of being easy to use: Just paste a URL or a section of text that you want to check. This well-known service is basically free. For more functionality, you will have to take a pro version.

2. Plagiarism Detect
Plagiarism Detect is a premium service. Signing up is done through a quick and easy process, and you can check an unlimited number of pages once your account is created.

The cost per page is $0,50, and each analysis will take a minimum of five to seven minutes. If you plan to do a lot of research this tool is probably not the first choice for the amateur blogger.

3. Article Checker
ArticleChecker is a free online service that is very easy to use. Simply copy and paste the blog post you want to check into the text box on the site, or provide the URL of the article and click "Compare."

You can also choose to check your text using Google or Yahoo Search. And for added protection, you can choose to run your search twice, once in each search engine.

If matching phrases are found, the results will show the number of times the content appears online. Although this tool is very easy to use, you have no way of controlling the level of sensitivity of the research you conduct. It can therefore miss results that other tools would see.

4. Duplichecker
Duplichecker is a free online service that allows you to copy and paste your text, download the article file, or enter the URL of the site you wish to check.

Non-registered users can perform three searches per day. Registered users can perform unlimited searches. The service checks each piece of text line by line for duplicates, which suggests the job is a bit more in-depth than with other tools.

5. Plagiarisma
Plagiarisma has the advantage of supporting over 190 languages. This plagiarism checker allows users to check for duplicate content on Google or Yahoo by copying and pasting text into a text box, entering the URL to check, or uploading a file. The accepted file formats are: Doc, Docx, Rtf, Txt, Odt and Pdf.

Each query is limited to 5000 characters if you are using the free version of the tool. If you have a blog that has long articles that you want to check out, you'll need to run more than one text check, or register on the site. Registration is free and will give you better and faster results.

This tool will show you the results of Google and Yahoo, which will allow you to determine if the text has been copied word for word, or simply contains similar phrases in the blog you are browsing.

Registered users are able to use the service up to five times per day, which may not be enough if you have a large number of words to check, and need to do so on a regular basis. To access all the features offered by the service and do more research, you will need to take out a premium subscription.

Get to know your bloggers

Checking out a blogger's work is a good way to make sure they're up to the task, but there are some things you can do ahead of time to increase your chances of working with a quality blogger. Most importantly, the person should have some web writing experience, even if only for their personal blog.

Make reference checks an important part of making sure the people you work with are trustworthy. Someone who puts their personal life to a high standard, will likely have the same attitude towards their work.

Take the time to ask the authors a few questions, either by email, phone or Skype, to determine their level of knowledge regarding the importance of uniqueness of content and meeting deadlines. For your part, have a copyright and plagiarism policy that explains how you check and respond to any illegal content.

Removing the temptation to copy "just this once" text from a blogger rushing to meet a deadline can nip the problem in the bud.

Don't underestimate the value of original content. Aside from its potential rankings, this is probably the best way to manage the reputation of your blog. So, it's worth it!

Follow this simple rule: better check twice than to be penalized once. Make content verification part of your daily routine.