How to Automatically Replace Numeric Citations with Citation Keys in LaTeX Using PowerShell

We’ve all been there. You’re wrapping up a paper in LaTeX, and you realize your document is full of \cite{1}, \cite{2}, \cite{3}… but your .bib file uses proper keys like smith2023keyword. Now you’re staring at dozens — maybe hundreds — of citations that need fixing, one by one.

I ran into this exact problem while working on a manuscript last year. After spending way too long doing it by hand (and making a few mistakes along the way), I wrote a short PowerShell script to handle it automatically. It saved me a ton of time, and I think it might help you too.

What’s the Problem, Exactly?

Here’s what it usually looks like. Your .tex file has something like this:

Recent advances have revolutionized the field \cite{1}\cite{2}.

Meanwhile, your .bib file has proper entries like:

@article{smith2023keyword,
  title={Title of the First Paper},
  author={Smith, John and Lee, Jane},
  journal={Journal Name},
  year={2023}
}

See the mismatch? Your document says \cite{1}, but it should say \cite{smith2023keyword}. When you only have a few references, it’s no big deal. But when you have 50 or 100? That’s where things get painful.

The Fix: A Simple PowerShell Script

The idea is straightforward — we tell the script which number maps to which citation key, and it does all the replacing for us. No more Ctrl+H marathons.

Before You Start

You’ll need:

• A Windows PC (PowerShell is already there)
• Your .tex file with numeric citations
• Your .bib file so you know the correct keys
• About 5–10 minutes

Step 1: Set Up Your Citation Mapping

Take a look at your .bib file and note down which number corresponds to which citation key. For example:

%1
@article{smith2023keyword,
  title={Title of the First Paper},
  author={Smith, John and Lee, Jane},
  journal={Journal Name One},
  year={2023}
}

%2
@inproceedings{doe2024analysis,
  title={Title of the Second Paper},
  author={Doe, Alice and Park, James},
  booktitle={Proceedings of the Conference Name},
  pages={100--115},
  year={2024}
}

So 1 maps to smith2023keyword, 2 maps to doe2024analysis, and so on. Just keep adding entries for as many references as you have.

Step 2: The PowerShell Script

Here’s the full script. You can copy it as-is and just update the mapping part with your own citation keys:

# LaTeX Citation Replacement Script
# Replaces \cite{number} with \cite{citationkey}

# Create the citation mapping (add as many as you need)
$citationMap = @{
    '1' = 'smith2023keyword'
    '2' = 'doe2024analysis'
    # '3' = 'your_next_key_here'
}

# Interactive file selection
Write-Host "Please select your LaTeX file..." -ForegroundColor Cyan
Add-Type -AssemblyName System.Windows.Forms

$openFileDialog = New-Object System.Windows.Forms.OpenFileDialog
$openFileDialog.Filter = "LaTeX files (*.tex)|*.tex|All files (*.*)|*.*"
$openFileDialog.Title = "Select your LaTeX file"

if ($openFileDialog.ShowDialog() -eq 'OK') {
    $inputFile = $openFileDialog.FileName
    $outputFile = $inputFile -replace '\.tex$', '_updated.tex'

    Write-Host "Selected: $inputFile" -ForegroundColor Green
} else {
    Write-Host "No file selected. Exiting." -ForegroundColor Red
    exit
}

# Read the file
Write-Host "`nProcessing file..." -ForegroundColor Cyan
$content = Get-Content $inputFile -Raw

# Count citations
$beforeCount = ([regex]::Matches($content, '\\cite\{\d+\}')).Count
Write-Host "Found $beforeCount numeric citations" -ForegroundColor Yellow

# Replace citations using regex
$pattern = '\\cite\{(\d+)\}'
$result = [regex]::Replace($content, $pattern, {
    param($match)
    $number = $match.Groups[1].Value
    $key = $citationMap[$number]

    if ($key) {
        return "\cite{$key}"
    } else {
        Write-Host "Warning: No mapping for citation $number" -ForegroundColor Yellow
        return $match.Value
    }
})

# Save the result
$result | Set-Content $outputFile -NoNewline

# Show results
Write-Host "`n✓ Replacement complete!" -ForegroundColor Green
Write-Host "Output: $outputFile" -ForegroundColor Green

Write-Host "`nPreview of replacements:" -ForegroundColor Magenta
$matches = [regex]::Matches($result, '\\cite\{[a-z]+\d{4}[a-z]+\}') | Select-Object -First 3
foreach ($m in $matches) {
    Write-Host "  $($m.Value)" -ForegroundColor White
}

Step 3: Running the Script

One-Time Setup

If you’ve never run a PowerShell script before, you’ll need to allow it first. Just do this once:

1. Press Windows + X and click Windows PowerShell (Admin)
2. Type: Set-ExecutionPolicy RemoteSigned -Scope CurrentUser
3. Hit Y and Enter

That’s it. You won’t need to do this again.

Actually Running It

1. Save the script above as replace-citations.ps1 — put it wherever you like
2. Right-click the file and choose Run with PowerShell (or open PowerShell and type .\replace-citations.ps1)
3. A file browser pops up — pick your .tex file
4. The script creates a new file called yourfile_updated.tex with all the replacements done

Your original file stays untouched, so there’s no risk of losing anything.

See It in Action

Click to see a Before → After example

Before (input.tex):

\documentclass{article}
\begin{document}

Some introductory text about the research topic \cite{1}\cite{2}.

Further discussion on methodology and results \cite{2}, particularly when
applied to analysis and evaluation \cite{1}.

\bibliographystyle{plain}
\bibliography{references}
\end{document}

After (input_updated.tex):

\documentclass{article}
\begin{document}

Some introductory text about the research topic \cite{smith2023keyword}\cite{doe2024analysis}.

Further discussion on methodology and results \cite{doe2024analysis}, particularly when
applied to analysis and evaluation \cite{smith2023keyword}.

\bibliographystyle{plain}
\bibliography{references}
\end{document}

Under the Hood (For the Curious)

You don’t need to understand this part to use the script, but if you’re curious about how it works, here’s a quick breakdown.

The Hashtable

$citationMap = @{
    '1' = 'smith2023keyword'
    '2' = 'doe2024analysis'
}

Think of this as a dictionary. The script looks up each number and finds the matching citation key.

The Regex Pattern

$pattern = '\\cite\{(\d+)\}'

This tells the script what to look for:

• \\cite — the literal text \cite
• \{ and \} — the curly braces
• (\d+) — one or more digits (this is what gets captured and replaced)

The Replacement

[regex]::Replace($content, $pattern, {
    param($match)
    $number = $match.Groups[1].Value
    $key = $citationMap[$number]
    return "\cite{$key}"
})

For every match, the script grabs the number, looks it up in the dictionary, and swaps it with the real citation key.

What If I Have a Lot of References?

No problem. Just keep adding lines to the mapping:

$citationMap = @{
    '1' = 'smith2023keyword'
    '2' = 'doe2024analysis'
    # ... keep going
    '50' = 'lee2024algorithms'
    '100' = 'wang2023method'
}

The script handles them all the same way, whether you have 5 or 500.

A Few Tips from Experience

Do:

• Always test with a small file first before running it on your full thesis
• Double-check your number-to-key mapping — a wrong mapping means wrong citations
• Use meaningful citation keys like smith2023keyword instead of vague ones like ref1

Don’t:

• Reuse the same citation key for different numbers
• Forget the quotes around numbers in the hashtable — write '1', not 1
• Worry if you see a warning — it just means the script couldn’t find a mapping for that number, and it leaves the original citation as-is

Common Issues (and Quick Fixes)

“Scripts are disabled on this system” Run this in PowerShell as Admin:

Set-ExecutionPolicy RemoteSigned -Scope CurrentUser

“Nothing got replaced” Check that your citations actually use the \cite{number} format. Also make sure there are no extra spaces inside the braces — \cite{ 1 } won’t match.

“Warning: No mapping for citation X” You’re using citation number X in your document but haven’t added it to the $citationMap. Either add it or leave it — the script won’t break anything.

Bonus: Combining Multiple Citations

The script handles back-to-back citations just fine:

Click to see an example

Before:

Multiple studies \cite{1}\cite{2} have shown...

After:

Multiple studies \cite{smith2023keyword}\cite{doe2024analysis} have shown...

Quick tip: After running the script, you can manually merge these into a single cite command:

Multiple studies \cite{smith2023keyword,doe2024analysis} have shown...

This gives you a cleaner output — [1,2] instead of [1][2].

Wrapping Up

Look, nobody enjoys spending their afternoon doing find-and-replace on citation keys. This script handles it in seconds, and once you’ve set up the mapping, you can reuse it anytime you work with the same bibliography.

Give it a try on your next paper — I think you’ll be surprised how much time it saves.

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Ready to Use It?

1. Copy the script into a .ps1 file
2. Update the $citationMap with your own citations
3. Run it on your .tex file
4. That’s it — you’re done

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Tip: Take a few minutes to get your citation mapping right. It’s worth the upfront effort — it’ll save you hours down the road.

Warning: Always keep a backup of your original .tex file before running any script on it, especially if it’s your final thesis or dissertation!

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Got questions or ran into something unexpected? Drop a comment below — happy to help.