As a fiction writer, one of the issues I seem to run into most often is not fully knowing the characters I create. Even when I think a character is fully developed, I find that I've passed over things like their past or the way they think or speak. To help both myself and other writers keep track of their characters, here are four online resources I've found helpful in writing fiction.
1. Charahub
One of the first steps to creating a story is coming up with your cast of characters, which is exactly what Charahub is made for. The site creates a map of the characters in your story and allows you to make a profile for each one, filled with the details of the character, from the deadly sin you believe represents them best to their opinions on love to their least favorite color. Some of the questions may seem unrelated or silly, but they force you to think about your character and every piece of their personality so that they can become real for you and your reader. If the question is something a person in the real world would be able to answer, it is something your character should be able to confront, too.
2. The "Mary Sue" Test
Now that you've answer the question of who this character is, you've got to figure out if the character you've created is as three-dimensional as you hope they are. One of the most common mistakes in writing original characters is allowing them to become a "Mary Sue," AKA a character who is not believable because of the way they are treated by their author, especially one that is created for readers to "admire, envy, or pity rather than empathize with." This test on Springhole.net allows you to run through a list of common traits in Mary Sue characters and check off all that apply to your creation. The test is extremely detailed and fairly lengthy, but if you want to make sure your character has been well-made, you should take part one, two, and five. Not every point on the list is something I would consider an aspect that makes a character flat, but when you begin to take note of all of the slight flaws piling up, it's easier to clean them from your character and make sure to avoid them in the future.
3. Celtx
Celtx is actually a website meant to be used for writing scripts, but it can be extremely helpful in developing the way your character speaks. It is far too easy to fall into a style of dialogue and make every character sound the same, even if they are each completely different people after going through the past two modes of character development. Celtx automatically formats dialogue into a script format, so you're able to write dialogue heavy scenes or just create dialogues as practice until you understand each character's voice without having to worry about anything but the dialogue. Your character's voice and tone are extremely important to their personality and how they come across, so using a program like Celtx to create a screenplay or script for a scene so that you can really develop the way the characters talk can help you make sure the traits you created for them in your planning process actually make it onto the page.
4. Pinterest
At this point, basically everyone has heard of Pinterest, though not normally in the context that most writers tend to use it. For most, Pinterest is used as a source of inspiration, whether that is through DIYs, quotes, art, or photography, but writers have begun to take the latter in order to create boards dedicated entirely to their original characters. Some use it to collect images of people who match their character's physical description or quotes that inform the way they depict them, but one of the best uses I've found to fully create a character is to create a board that matches the tone and aesthetic of the character. Following photography and aesthetic based users--normally those who are either writers themselves or who create boards for fictional characters that already exist--will fill your dashboard with images to help you establish your character's personality based entirely on visuals. Some boards are comprised of pictures like dark swimming pools and melting popsicles while others are filled with the likes of pale pink Tamagotchis and silver knives. Writers take any image that reminds them of their character in any way, shape, or form and create an entire page dedicated to them, which really helps in understanding a character in a way similar to the way Charahub does. You are able to see the little details about a character when you are able to look at a photo of a bundle of red feathers and connect it to their name.
You can use every one of these resources or just one, but I can tell you from experience that each one of them will help you develop your character until they are as fully recognizable as someone you could meet in real life.