The easiest way to ensure your script is formatted correctly is, of course, to use screenwriting software. Examples include: CeltX, Movie Magic, Writer Duet, and Final Draft. Those programs automatically format everything correctly so you can focus on writing. And some of them are even Free!
However, if you insist on using Word or some other program not designed to write screenplays, here's what to know:
Length: Feature scripts should be 90-120 pages. Yes, we know that A QUIET PLACE was 67 pages and THE SOCIAL NETWORK was 163. If you are not famous or don't have a fancy agent, then just stick to 90-120. If you don't, be advised that producers will generally groan about anything over 110 pages and simply not read anything that's higher than 125. (Another way to think about it: the typical script is 18,000-20,000 words.)
Font: 12-point Courier
Left Margin: 1.5 inches (Because we used to bind scripts with brads!)
Right Margin: 1 inch
Top / Bottom Margins: 1 inch
Dialogue: All dialogue gets indented further in, 2.5 inches from the left side of the page.
Page Numbers: Below in the top-right corner, 1/2 inch from the top of the page. Do not number the cover page. All page numbers get a period afterwards.
Here's a super helpful overview of the anatomy of a script page from Studio Binder.
And here's a short screenplay from the Academy of Arts and Sciences (The Oscars) that cheekily explains screenplay formatting while telling a story.
When a character is first introduced in your script, their name should be capitalized, followed by their age in parenthesis. That looks like this: CAROL (mid 30s, Indian) kicks open the saloon doors and grunts her order at the barman.
It's generally helpful to state the character's race. This encourages more diverse casting as characters have historically been assumed white unless otherwise specified.
Pro Tip: your lead characters should have memorable introductions. They should make a striking first impression if they are going to be important to your story. What does their appearance tell us about what kind of person they are?
Here's a terrific character introduction from the screenplay APEX by Jeremy Robbins.
Here's an excellent character introduction/description from the market draft of the screenplay AIR JORDAN by Alex Convery (which was produced as AIR).
SLUGLINES / SCENE HEADINGS
Your Scene Headings should read EXT. or INT., followed by the location, followed by a dash, followed by either DAY or NIGHT. It looks like this: EXT. NEW YORK CITY SIDEWALK - DAY
The DAY and NIGHT part is used for production purposes, so we generally recommend sticking to one or the other. LATER or CONTINUOUS can be used sparingly.
Sluglines should be bolded. Bolding plus underlining is a bit much, in our opinion.
If you're moving around to different areas in the same location, you can use a Sub-Header. That's placed exactly where a regular slugline would be, but you don't need to restate the EXT/INT or DAY/NIGHT parts because they're understood to be unchanged. Common examples include BATHROOM, KITCHEN, HALLWAY, OVER BY THE STREETLAMP etc.
Here's an example of a properly formatted subheader from the original spec screenplay BELLA by Chris Grillot.
You can also incorporate it into a regular Scene Heading like in this example below, from A QUIET PLACE by Bryan Woods and Scott Beck.
Here's an exterior example from the same script:
Usually, you'll indicate a montage is about to happen in your action description using "Begin MONTAGE" and then provide a dashed list of shots, like this example from the original spec screenplay BELLA by Chris Grillot.
Here's another example that uses "Quick Series of Shots" from the original spec screenplay BELIEVE ME by Dreux Moreland & Hannah Mescon.
If you'd like to tell your reader that the following scene - or part of it - will be spoken in another language, you can do just that in the action description, using Italics to delineate the non-English language dialogue from that point forward. (It's much easier than writing the language in parentheticals under every line of dialogue.)
An example of non-English language denoted in the original spec screenplay RUIN by Ryan Firpo.
Another example of non-English language denoted in the original spec screenplay NOMADS by Esteban Orozco.
Directing the Performance
Anything that tells the actor how to say the line is generally frowned upon. Avoid using parentheticals in your dialogue to convey how the line is delivered. So stuff like (sotto), (sarcastically), (under her breath) etc., should be avoided. If you've conveyed who your characters are in their descriptions, settings, context, and in the way they act and react to their environments, then much of this will already be infused in the lines. Also, we highly advise against using too many exclamation points. It starts feeling melodramatic pretty quickly.
If you are not an established writer/director, we generally recommend avoiding camera angles, or using them very sparingly. Generally speaking, camera angles should be conveyed implicitly by the way the action description is written. So, if the action description reads, "His diamond earing glints in the sun," what kind of shot do you think that is? Close or wide? If the action description reads, "In the distance, a lanky silhouette slowly makes its way across the moonlit plain," would you say that's close or wide?
Some people use this at the end of every scene. Don't do that.
"Unfilmables" are pieces of information in a script that can't be visualized on screen, and they are generally a no-no. The classic example is characters' thoughts or feelings. In a novel, you can write them into the prose and that's okay because the end-user, so to speak, is someone reading your book. In a script, however, it needs to be clear how an audience would receive that information. E.g. "He hated the way Carl was speaking to him because it reminded him of his Papa." How would your audience experience that information on screen? Information can be conveyed through Dialogue, stated in V.O., demonstrated through character action, production design, written as a SUPER, or otherwise visualized on screen. Other examples of unfilmables include omniscient information. E.g. "Elizabeth is Caitlyn's girlfriend and they have been dating for twelve years." For this example, their romantic relation to one another should be conveyed by their interactions and greater context, and the long-term status of their relationship would probably need to be conveyed in Dialogue, if necessary.
Adhering to these standards will help you get past the gatekeepers so someone can actually read your script. But they also make the reading experience much easier on the working professionals who must work within industry standards. It's also a signal to anyone who gets your script that you know what you're doing. Any deviations from these standards may suggest to your reader that they're not in sure hands, which causes them to disengage. All that said, focusing on a bunch of rules when you're trying to be creative can be overwhelming and discouraging. So do whatever you have to do to get into a groove, have some fun, and generate some pages. Just make sure that, before you send it to an industry professional, the script adheres to the above standards.
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