There are many factors to consider when deciding how much to charge for editing English texts. Some of these factors include the length of the text, the level of editing required, the deadline, and the author's budget.
Typically, editors charge by the word, by the hour, or by the project. For example, a standard rate for editing a 5,000-word document might be $0.02 per word, or $100 for the entire project. However, rates can vary depending on the factors mentioned above.
If you are unsure of how much to charge for a particular project, it is always best to ask the author for their budget upfront. That way, you can tailor your services and pricing to meet their needs.