ABBYY FineReader Open Source Alternative: OCRmyPDF
By Schema LawPublished Updated
The nearest open source alternative to ABBYY FineReader is OCRmyPDF, a command-line program that uses the Tesseract engine to add a text layer to scanned PDFs. It replaces one FineReader job, making scans searchable. It has no editor, no document comparison and no Word export, and someone in your office has to install and maintain it.
This post describes OCRmyPDF and Tesseract only from the projects' own documentation, and FineReader only from ABBYY's user guide. No accuracy comparison appears here, because none of those sources publishes one you could rely on for your own documents. The useful comparison is about what each tool is for and who has to look after it.
Is there an open source alternative to ABBYY FineReader?
Yes, for one part of what FineReader does. OCRmyPDF's documentation describes it as "a Python application and library that adds text 'layers' to images in PDFs, making scanned image PDFs searchable." It relies on Tesseract, which its own manual calls "an open source text recognition (OCR) Engine, available under the Apache 2.0 license."
The two projects divide the work.
| Project | What its documentation says it is | Licence stated by the project |
|---|---|---|
| Tesseract | A recognition engine used from the command line or through an API "to extract printed text from images". The manual says it "doesn't have a built-in GUI". | Apache 2.0 |
| OCRmyPDF | A tool that takes a PDF, runs Tesseract on each page, and puts the recognized text back into the PDF | Mozilla Public License 2.0 |
Those statements come from the Tesseract user manual, the OCRmyPDF introduction and the OCRmyPDF repository on GitHub, whose README states the licence and adds that the software is distributed on an "AS IS" basis, without warranties of any kind.
If you searched for an ABBYY FineReader free alternative, be clear about what "free" buys. There is no licence fee for either project. There is also no installer with a wizard, no window with buttons and no vendor help desk. OCRmyPDF's README calls it "a scriptable command line program", and that phrase is the whole user interface.
For what FineReader is and which editions exist, see the post on ABBYY FineReader PDF. If you are open to paying for a different product, the post on paid alternatives to FineReader for law firm workflows covers that question.
What OCRmyPDF does to a scanned PDF, in its documentation's words
OCRmyPDF renders each page as an image, recognizes the text, and puts that text back into the same PDF. The introduction says it "performs OCR on the rasterized image to generate an OCR 'layer'" and that "This layer is then integrated back into the original PDF." The scan stays visible; the words sit behind it.
The text layer
The README lists the features that matter to a file room: it "places OCR text accurately below the image to ease copy / paste", "keeps the exact resolution of the original embedded images", and, "when possible, inserts OCR information as a 'lossless' operation without disrupting any other content". The introduction makes the same point from the other side, saying OCRmyPDF "can produce a minimally altered PDF as the output" where a do-it-yourself pipeline would generate a new PDF and could lose details such as the document's metadata.
That matters for an exhibit. You want the page image you received to be the page image you keep. The guide to making a scanned PDF searchable explains why the image should stay identical and how a text layer is built.
When the command finishes, open the output and look up the exhibit number, the party names in the caption, and a short phrase from the complaint. Check the deposition date and the affidavit signature line on the page image. If one of those searches misses, run the file again or fix the page before you trust the text layer.
The PDF/A default
OCRmyPDF's output is PDF/A unless you say otherwise. The introduction states that "OCRmyPDF defaults to generating PDF/A-2b" and that you can turn this off with the --output-type pdf option. The same page lists drawbacks: some viewers show an alert for PDF/A files, the files tend to be larger, and PDF/A files "can be digitally signed but may not be encrypted".
Whether you want PDF/A depends on where the file is going. Check your court's or agency's filing rules for the format it requires; the post on what PDF/A is explains the standard and its conformance levels.
What a run looks like
The cookbook in the documentation gives the basic commands. Three to know first:
# Add a text layer and write a PDF/A file
ocrmypdf input.pdf output.pdf
# Add a text layer and keep an ordinary PDF
ocrmypdf --output-type pdf input.pdf output.pdf
# Straighten crooked pages before recognition
ocrmypdf --deskew input.pdf output.pdfThe OCRmyPDF cookbook also documents a --sidecar option that writes the recognized text to a companion text file, and a language option: it says OCRmyPDF "assumes the document is in English unless told otherwise" and that "Language packs must be installed for all languages specified." A Spanish-language record run with the default setting is a predictable source of bad text.
What does the OCRmyPDF documentation say it cannot do?
The introduction has a section headed Limitations, and it is blunt. It says OCRmyPDF "is subject to limitations imposed by the Tesseract OCR engine", then lists them. The ones a law office will meet first are handwriting, reading order and document structure.
Here is that list, quoted from the project, with what each item means for a legal file.
| The documentation says | What it means for your documents |
|---|---|
| "It is incapable of recognizing handwriting." | Handwritten notes, margin annotations and filled-in forms get no usable text from this route |
| "It may detect gibberish and report it as OCR output." | A stamp, a signature or a smudge can come back as nonsense characters in the text layer |
| "Results may be subpar when a document contains languages not specified in the -l LANG argument." | Whoever runs the job has to know the language of each document beforehand |
| Tesseract "might fail to recognize two columns in a document and attempt to join text across columns." | Text copied from a two-column page may run across both columns line by line |
| "the quality of the OCR output depends on the quality of the input." | Faint faxes and poor photocopies produce poor text |
| "Tesseract does not divide text into paragraphs or headings." The generated PDF "does not contain any information about the document's structure." | You get searchable words in position, with no notion of a heading, a clause or a table |
| "The OCR accuracy may not match that of commercial OCR solutions." | The project itself tells you to test before you rely on it |
Read the last row as the project's caution about its own engine, stated in general terms. It names no product and gives no figure, so it tells you nothing about how any particular commercial tool will do on your scans. Only a side-by-side test on your own pages answers that.
The structure limit deserves a second look, because it sets the ceiling on what you can do afterwards. A text layer without structure is fine for finding a word. It is not a route to a table of payments in a spreadsheet or a lease in an editable document. The post on whether OCR can handle two-column documents explains reading order and how to spot text that was joined across columns.
One more statement belongs on this list, from the documentation's page on PDF security issues: "OCRmyPDF should only be used on PDFs you trust. It is not designed to protect you against malware." Productions from the other side are files you did not create. Follow your firm's rule for scanning incoming files before any tool opens them.
FineReader features that OCRmyPDF and Tesseract do not replace
OCRmyPDF and Tesseract do not replace FineReader's PDF editor, its OCR Editor for correcting recognized text, its conversion to Word and Excel, or its comparison of two versions of a document. ABBYY's user guide lists all four. OCRmyPDF's documentation describes one output, a PDF with a text layer, plus an optional text file.
ABBYY's own summary is on the About ABBYY FineReader page of its user guide. Set against the open source documentation, the gaps look like this:
| What ABBYY's guide says FineReader PDF can do | OCRmyPDF and Tesseract, per their documentation |
|---|---|
| "Edit text (even whole paragraphs, also within table cells), hyperlinks, and pictures throughout a document" | No editor. The Tesseract manual says it has no built-in GUI |
| "Export PDFs into Microsoft Word, Excel, or another editable format" | Output is a PDF, with an optional plain text sidecar |
| "Quickly check how recognized text matches up with the original document and make any necessary changes with a built-in text editor and verification tools before saving" | No review screen. You open the output and check it yourself |
| "Identify differences in the text from two versions of the same document" | Not a feature of either project |
| "Remove sensitive information from documents through redaction" | Not a feature of either project |
| "Add watermarks, headers and footers, bates numbering, and stamps to PDFs" | Not a feature of either project |
| ABBYY Hot Folder "watches for documents in user-defined folders and converts them on a schedule" | A watched-folder script is documented, with caveats |
Two notes keep that table fair. ABBYY's page marks comparison and Hot Folder with a footnote: "This feature is not available with all versions of ABBYY FineReader." So check the edition before you assume a licence includes them. And the watched folder on the OCRmyPDF side is real but rough: the documentation's page on batch processing warns that the watching program it uses "may not work properly on a networked file system" and tells you to "disable your watched folder if you are doing anything other than copying files to it."
The FineReader post explains how the OCR Editor differs from the PDF editor and what the Hot Folder automates. If your only contact with FineReader is the copy that came in a scanner box, that is a different edition again; the ScanSnap post covers ABBYY FineReader for ScanSnap and what it adds to ScanSnap Home.
A quick way to decide which side of the line you are on
Write down the last five things you used FineReader for. Sort each into one of two piles.
- Pile one: "make this scan searchable." Incoming productions, closed-file archives, scanned mail. OCRmyPDF's documented job.
- Pile two: everything else. Fixing a recognized paragraph, turning a scanned agreement into a Word draft, comparing a signed copy with the last draft, redacting, stamping numbers.
If pile two is empty, an open source route can work. If it is not, you are replacing only part of the product and will need something else for the rest.
Who installs and runs a command-line OCR tool in a law office?
A command-line OCR tool needs someone comfortable with a terminal, package managers and scripts, with the rights to install software on the machine. On Windows, the OCRmyPDF documentation says that "there is no single command to install OCRmyPDF and all of its dependencies". In an office with no such person, a command-line tool is not a realistic choice.
What installation involves
The OCRmyPDF installation page gives one-line installs for macOS with Homebrew and for several Linux distributions. For native Windows it lists separate steps: install Tesseract, install the uv tool, install Ghostscript by hand because, in the page's words, it "is not available from winget", then install OCRmyPDF itself and confirm it with ocrmypdf --version. The page also describes running it through Windows Subsystem for Linux or a Docker image.
These are steps for whoever administers your computers. On a firm-managed laptop, ask whether you are allowed to install any of it before you try.
What running it involves
Each job is a typed command or a script. Consider a fictional three-lawyer firm, Brandt Halloran, that receives a production of 140 separate scanned PDFs. To process the folder, someone has to:
- Copy the files to a working folder, leaving the originals as received.
- Decide the options: language, PDF/A or ordinary PDF, whether to deskew.
- Run a loop over the folder. The batch page gives the Windows form,
for /r %%f in (*.pdf) do ocrmypdf %%f %%f, which processes files in place, so the working copy matters. - Read the messages for each file and note which ones failed or were skipped.
- Open a sample of the outputs, search for words visible on the page, and compare.
- Record what was run and with which version, in case anyone later asks how the searchable copies were made.
A job like that is routine for the person who wrote the script. The question for the firm is what happens in the week that person is away. The post on converting scanned PDFs with a Python script covers who maintains the script and what a silent failure looks like.
Questions to settle before you start
- Who installs it, and on which machine?
- Who updates Tesseract, OCRmyPDF and the language packs, and how will you know an update changed the results?
- Where do client files sit while they are processed, and who can reach that folder?
- Who checks the output, and against what?
- Who do staff ask when a file fails?
Free software versus a FineReader license: the costs that are not the price
The licence fee is the only cost that open source removes. Staff time to install, script, run and check, the lack of a help desk, and responsibility for updates all move to your firm. Whether that is cheaper than a licence depends on who would do the work and what else they would be doing.
Lay the two columns side by side and fill in your own numbers.
| Cost | OCRmyPDF and Tesseract | A FineReader licence |
|---|---|---|
| Purchase price | None | See ABBYY's pricing page |
| Installation | Your own time or your IT provider's | An installer from the vendor |
| Training | Command-line basics for whoever runs it | A desktop application with a user guide |
| When something fails | The README says to "report issues on our GitHub issues page"; it also invites business enquiries about consulting | Whatever support your ABBYY licence terms include; read them |
| Warranty | None. The README says the software is provided "AS IS" | As stated in ABBYY's licence terms |
| Updates | You choose when, and you retest | Per the vendor's release and licence model |
| Work the tool cannot do | Editing, Word export, comparison and redaction need other software | Covered to the extent your edition includes them |
Three hidden costs to price honestly
The single point of failure. A script that one associate wrote is firm infrastructure with one maintainer. Write the procedure down, including the exact command, and have a second person run it once.
Checking time. Neither route removes the need to read recognized text against the page. A tool with no review screen puts all of that checking in a separate viewer, on your clock.
The second tool. If you still need Word output or a comparison for some matters, you are paying for something else anyway. Count it.
When neither fits
Some offices want neither a command line nor a desktop suite to administer. A hosted converter is a third route: you upload the scan in a browser and export the result. Schema Law works that way, reading PDF, PNG or JPEG files into text and tables and exporting searchable PDF, Word, plain text and five other formats on every plan. The Free plan allows one document a day of up to three pages, which is enough to run the same test page through each route you are weighing; the pricing page lists the page allowances of the paid plans.
Whichever route you pick, run the same few pages from a real matter through it: a clean typed letter, a fax, a two-column page, a page with a stamp over text, and a form with handwriting. Then search each output for words you can see. The results on your own paper are the only comparison that counts.