"on a equal level" is correct and can be used in written English.
Example sentence: We are working together on a equal level to achieve our common goal.
By eliminating the traditional predominance of the medical division over the remaining ones of the hospital, putting them all on an equal level, it was hoped that a more collaborative working environment would emerge, to the general satisfaction of everyone involved.
"If I could detect that there was a chip on their shoulder, or that they were [asking me] with political motives, then I would probably say no...If I could have a conversation like the one we're having now, I could probably meet them on an equal level".
Existing on an equal level with reality, it becomes a reality in itself.
I was becoming increasingly frustrated that I couldn't compete with my mates on an equal level.
Rodriguez was a stride ahead, but he kept turning toward Jeter, kept working at ensuring that the conversation was on an equal level.
The matching of talent makes or breaks a new string quartet, and the young Alianza players seem on an equal level.
It must have been the first time they'd been spoken to on an equal level … it's a powerful message".
When Afghan women saw me walking around the center, working with men on an equal level, they saw a symbol of what the future can be.
He promoted Mr. Gundotra to senior vice president this year, placing him on an equal level with the heads of Google's core products like search and ads.
If adults can sit down and have book discussions and talk with other adults on an equal level about a wonderful book that they read, parents can do that with children, too.
The classical mainstream of theatre music in the West extends from the mid-17th century to the 1930s, and the instances of drama and music meeting on an equal level of imagination are relatively few.
