Read the code before you trust the file
The download is plain text, so any text or code editor opens it. You can read what a script would do without opening the PDF in a reader that might run it.
Show JavaScript
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Or start from a blank IRS form
Browse all IRS forms →- You add
- One PDF
- You set
- Nothing, there are no options
- You get
- The embedded scripts as a .js file
A PDF can carry JavaScript that runs inside a PDF reader, for example to show a message when the file opens. Show JavaScript pulls that code out so you can read it. You add one PDF and run the tool, and the code downloads as a text file with the .js extension. There are no options to set. The tool only reads: it does not run the code, judge it or remove it. A single file needs no account. To strip scripts from a document, Sanitize PDF has a Remove JavaScript option.
What can you do when you show a PDF's JavaScript?
Keep the scripts as a separate file
The code arrives as its own .js file, apart from the document. You can attach it to a ticket, store it with an audit record or pass it to a colleague who reviews code.
Start with nothing to configure
Show JavaScript puts no boxes or menus in front of the run. Add the PDF, press Run Show JavaScript and the job starts.
Look again after cleaning a file
After you remove scripts with another tool, send the cleaned PDF through Show JavaScript once more and compare the new download with the first one.
What showing JavaScript keeps and what it changes
Stays the same
- The PDF. The scripts stay in it and nothing is removed or switched off.
- The file on your device.
- Every page and every form field.
Changes
- The output is a plain text file with the .js extension, and no PDF comes back.
- Each script is written under a comment line naming your file and the script's name in the PDF.
- Only the document-level scripts are collected, those in the PDF's named JavaScript list. Scripts tied to a form field, a button, a page or the open action are not listed.
- When no such script exists, the file holds a single line saying the PDF does not contain JavaScript.
How to show the JavaScript in a PDF in 3 steps
Choose the PDF
Drop the PDF you want to inspect on the upload box, or select Choose file.
Start the extraction
No settings appear for this tool. Press Run Show JavaScript and wait for the progress bar.
Download and read the code
Select Download to save the .js file, then open it in a text editor. Read it there and do not run it.
Why show PDF JavaScript with indox?
JavaScript in a PDF is not part of the visible pages, which is why a separate look is useful. This page gives you a direct way to take that look. It accepts one PDF and hands back the code as text, with no settings between you and the result. The download is a separate file, so you can review it with the tools you already use for code. One file runs without an account, the PDF is sent to indox over HTTPS, and free-tier uploads and their script files are deleted automatically within 24 hours after the job finishes. The tool stops at showing. Removing scripts is a different job, and this page tells you where to find it.
- Scripts delivered as readable text
- A separate .js file to keep
- Nothing to configure
- The PDF itself is left alone
- One file runs without an account
What are the limits when you show a PDF's JavaScript?
- Size
- The free tier has a file size limit. Signing in raises it, and paid plans raise it further.
- Formats
- This tool works on PDF files. To change a file's type, use the PDF converter.
- Privacy
- Files are encrypted in transit and processed on indox infrastructure.
- Deletion
- Free-tier files are deleted automatically within 24 hours after the job finishes. Signed-in output stays in your history for your plan's retention period.
Limits worth knowing
- The tool shows scripts and does not remove them. To delete them, use Sanitize PDF, which has a Remove JavaScript option and carries the Pro badge in the tool catalog.
- It does not say whether the code is safe or harmful. You or a reviewer have to read the file and decide.
- When the PDF has no document-level script, the download holds a single line saying the PDF does not contain JavaScript. Scripts tied to form fields, buttons or pages are not collected.
- The download has the .js extension, yet the page calls the output format PDF and says a PDF file is ready. Expect a text file.
- This page cannot take a password. If the PDF asks for one when it opens, unlock it with Unlock PDF before you look for scripts.
When the result is not what you expected
| What you see | Why | What to do |
|---|---|---|
| The download says the PDF does not contain JavaScript | No document-level script was found | Scripts on form fields or pages are not collected here. To remove all kinds, run Sanitize PDF. |
| The file opens as text, not as a PDF | The output is a .js file | Open it in a text or code editor, not in a PDF viewer. |
| You want the scripts gone | This tool only shows them | Run Sanitize PDF with Remove JavaScript ticked. |
| The file asks for a password | The page has no field for one | Remove it with Unlock PDF, then look at the open copy. |
What do the free and paid plans add?
Free
- All converters
- Daily credit refresh
- Email support
Basic
- Access to all features
- AI Extract
- Priority conversions
- Email support
Highest priority
Premium
- Everything in Basic
- Highest priority queue
- Larger file limits
- Priority support
Pay-As-You-Go
- No subscription
- Credits never expire
- Opt-in auto-refill
- Access to all features
What else can you do with a PDF?
Who looks at the JavaScript in a PDF?
IT and security staff
An attachment from outside the company is flagged for review. Extract its scripts and read them as text before anyone opens the document.
Form designers and developers
A fillable form misbehaves and you need to see the code behind it. The .js file puts the scripts in an editor with search and line numbers.
Cautious recipients
You received a PDF you did not expect and want to know whether it carries code. Run it here first and look at what comes back.
When to show JavaScript, and when to pick another tool
- A PDF from an unknown sender needs a look before it is opened on a work computer.
- An audit asks for evidence of the script code a published document contains.
- The buttons or calculations in a form act oddly and the script has to be read.
- You cleaned a file and want to see what a second extraction returns.
- You only need to know whether scripts exist. Get PDF Info lists JavaScript in its report, next to attachments and metadata.
Where can I read more?
Sources
- ShowJavascript source, v2.14.2Stirling-PDF on GitHub
- Stirling-PDF documentationStirling-PDF
Facts checked on October 16, 2026
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Show JavaScript FAQs
What does Show JavaScript give me?
A text file with the .js extension that holds the JavaScript found in your PDF. You download it and open it in an editor.
Does the tool remove the scripts?
No, it only shows them. Your PDF keeps its code. Sanitize PDF has a Remove JavaScript option for that job.
Is it safe to open the downloaded file?
Open it in a text editor to read it. Do not double-click it or run it, because some systems treat a .js file as a program.
What if my PDF has no JavaScript?
The download is a short text file with one line saying the PDF does not contain JavaScript. Only document-level scripts are collected, so scripts tied to form fields, buttons or pages are not listed.
Can it tell me whether the code is dangerous?
No. The tool makes no judgment about the scripts. It hands you the text so that you or a specialist can review it.
Are there any settings to choose?
None. You add a PDF and press Run Show JavaScript, and that is the whole procedure.
Can I inspect a password-protected PDF?
Remove the password first. Nothing on this page accepts one, so use Unlock PDF and then run the unlocked copy here.
What happens to the PDF I upload?
It travels over HTTPS, and one file runs without an account. On the free tier, indox deletes the PDF and the script file automatically within 24 hours after the job ends.