If you want to add some style and variety to your writing, then it's essential to broaden your vocabulary. One way to do this is by finding synonyms for common words such as "unbelievable." Some synonyms for "unbelievable" include incredible, astonishing, remarkable, astounding, extraordinary, mind-blowing, staggering, and fabulous. Each of these words carries a unique connotation and can help you convey the degree of your disbelief or amazement. For example, "incredible" suggests something that is hard to believe due to how impressive it is, while "mind-blowing" suggests an overwhelming level of awe and surprise. By using synonyms for "unbelievable," you can enhance your writing and keep your readers engaged.