A lot of big companies filter and rank the CVs they receive for their job ads using a keyword-based algorithm. This means that to be noticed, your resume must be tailored to that particular job description.
With this in mind, Jobscan's tool helps you optimize your CV to do well in an ATS (applicant tracking system).
All you need to do is upload your CV (file or text) and paste the job ad text. You will get a match rate (Jobscan recommends aiming for at least 80%) based on the fit of hard skills, education level, job title, soft skills, other keywords.
There's also a Recruiter Findings section, checking for things that the people behind the ATS usually notice, such as word count of your CV, measurable results, job level match, etc. The free version lets you compare 5 match rates on sign up and then 2 every month.
Their
Learning Center has tips to help you create your CV, Cover letter, LinkedIn and to nail your job search.
People wanting to customize their CV to a job offer.