To use the Ahrefs SEO tool for free, you can take advantage of their 7-day trial offer. Here's how you can sign up and start using Ahrefs:

1. Go to the Ahrefs website (https://ahrefs.com/).
2. Click on the "Start 7-day trial" button.
3. Fill in the required information to create an account.
4. Provide your payment details, as Ahrefs requires this information to start the trial. Don't worry, you won't be charged during the trial period.
5. Once your account is set up, you'll have access to the full range of Ahrefs' SEO tools for the next 7 days.

During the trial period, you can explore various features of Ahrefs, such as:

• Site Explorer: This tool allows you to analyze backlinks, organic search traffic, and keywords for any website.
• Keyword Explorer: With this tool, you can find new keyword opportunities, analyze keyword difficulty, and get search volume data.
• Content Explorer: Use this tool to discover popular content in your niche, analyze its performance, and find potential content ideas.
• Rank Tracker: Track your website's rankings for specific keywords and monitor your SEO performance over time.

Remember, the trial period is a great opportunity to explore Ahrefs and determine if it meets your SEO needs. Make sure to take advantage of the tools and gather relevant data during this time.

For more information and updates on Ahrefs' pricing and plans, you can refer to their pricing page.

Hope this helps! Enjoy your Ahrefs trial!