Just having an idea isn’t enough when you want to write a book. You have to decide whether your story idea is strong enough – can you turn it into a book of 50k words or more? If you choose a weak idea, you could find yourself giving up on the book while writing it, or you could finish writing it but find it lacking. So, how do you know if your story idea is strong enough? When I’m deciding what type of manuscript to write next, I find it helpful to think about these things.
The specifics
If your idea is too vague, it won’t have legs to stand on. You might want to write about a treasure hunt in a jungle, but maybe that’s all you know. A good activity to start with is thinking about the specifics and asking yourself questions: who are your characters? Where will the story take place? Why is this story important – what’s its purpose? What are your characters up against?
If you find yourself unable to flesh things out further than a brief idea for a setting or a character, you might need to wait and hold onto them. Save those elements until you know how to fit them into a wider story. Other ideas will come along, and you can even merge them to come up with something unique later.
The main character and their goals
Is there something your main character really wants, and are there obstacles standing in their way? All stories are about problems. The messier and more complicated the problem, the more interesting the story. No one wants to read about someone having quite a happy life and getting everything they want easily – that’s boring. In Save the Cat! Writes a Novel by Jessica Brody, she says that you need to create a story-worthy hero with three ingredients:
- A problem or flaw to be fixed
- A want/goal
- A need or life lesson
These are great things to consider when you’re building your main character, because if you create someone who is flawed and who has big life problems, readers are going to be entertained. I’d only add that you need to make sure you give them something that makes them relatable or likeable. Give them a fun quirk, a tragically relatable past, or a trait that makes people warm to them, even if they’re supposed to be an unlikeable character.

Conflict
Just as your character should have major problems, your plot should be full of problems too. If everything goes smoothly and there are no hiccups, you’ll send readers to sleep. You don’t have to create disasters on a grand scale if you’re writing something character driven, but there should be some conflict. Ask yourself:
- What’s the main struggle? Is there an oppressive government, a villain on the loose, a dark wizard causing havoc? Is the struggle more internal – a problem with a romantic relationship, or someone struggling to get along with family?
- What’s at stake here? What do your characters stand to lose – their family, their dreams, their entire world, or just their integrity?
- How does the main plot impact your characters’ lives?
- What obstacles are stopping your character/s from reaching their goals?
The key thing to remember here is nothing should be easy. Make things hard, and don’t shy away from putting your characters through hell (cue evil laughter from writers everywhere). Even in a light and fluffy read, there are characters struggling with something.
Age category and genre
The age category and the genre of your work are important for knowing whether your idea is strong enough to turn into a full book. Middle grade fantasy books tend to be shorter than adult fantasy books, for example, so you’ll need a story that can fit into 50k words instead of 100k. And if you’re writing a character-driven romance, you probably won’t need as many complex plot details as if you’re writing a high fantasy or a complicated mystery. Keep this in mind when you’re developing ideas – you might find that your idea is better suited to a younger age category or a different genre entirely.

I hope these tips helped you! Do you have any other tips for deciding whether a story idea is strong enough? How do you decide which of your ideas to stick with?
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