Our reading of the responsibilities in each posting, not the employer’s title. Junior means guided work, mid means independent delivery, senior means leading an ambiguous project through production, and staff+ means leading across teams or projects.
A stated minimum is the employer's description of the work, not a filter you have failed.
The band a posting falls into is a floor, not a ceiling on the experience the employer will consider.
Two postings in the same band can differ on whether you would own a deployment or run one task inside it.
Nothing here tells you whether an employer will waive a stated year requirement, and only the employer can.
Read the work attached to the years
A posting asking for 4+ years belongs in the 3–5 minimum-years group. Look for the systems you would build, the customer or internal team you would support, and the ownership you would carry. A posting describing a narrow implementation task raises a different question from one expecting independent production delivery.