PDFluent vs pdf-rs

Both are Rust libraries. pdf-rs parses PDFs for reading; it cannot write, fill forms, validate PDF/A, or produce digital signatures.

pdf-rs is an open-source Rust crate for parsing and reading PDF files. It handles text extraction and document structure traversal well. It is read-only by design: there is no write API, no form filling, no PDF/A output, and no digital signatures. PDFluent covers reading, writing, form processing, validation, and signing.

Side-by-side

PDFluent
Rust
use pdfluent::PdfDocument;

fn main() -> pdfluent::Result<()> {
    let mut doc = PdfDocument::open("application.pdf")?;

    // Read
    let text = doc.page(1)?.text()?;
    println!("{}", text);

    // Write form fields
    let mut form = doc.form_mut();
    form.set_text("applicant_name", "Jane Smith")?;
    form.set_text("date", "2024-04-14")?;

    // Sign
    let signer = pdfluent::Pkcs12Signer::from_pfx_file("cert.p12", "password")?;
    doc.sign(&signer, pdfluent::SignOptions::new())?;

    // Validate PDF/A-2b before saving
    let report = doc.validate_pdfa(pdfluent::PdfAProfile::A2b)?;
    if !report.is_compliant() {
        eprintln!("Validation issues: {:?}", report.violations);
    }

    doc.save("application_signed.pdf")?;
    Ok(())
}
pdf-rs (Rust)
Rust
use pdf::file::FileOptions;
use pdf::object::*;

fn main() {
    // pdf-rs opens PDFs for reading only
    let file = FileOptions::cached().open("application.pdf").unwrap();

    // Traverse pages and extract text
    for page in file.pages() {
        let page = page.unwrap();
        // Content stream traversal - no high-level text API
        if let Some(content) = page.contents.as_ref() {
            println!("{:?}", content);
        }
    }

    // pdf-rs CANNOT write PDF files
    // pdf-rs CANNOT fill form fields
    // pdf-rs CANNOT add digital signatures
    // pdf-rs CANNOT validate or produce PDF/A
    // pdf-rs CANNOT flatten XFA forms
}

Feature comparison

FeaturePDFluentpdf-rs (Rust)
PDF parsing / reading
Text extraction (high-level API)Low-level only
PDF writing
AcroForm filling
XFA forms
Digital signatures (PAdES)
PDF/A validation
WASM targetPartial

Pros and cons

PDFluent

  • Writing, editing, and saving PDFs — pdf-rs cannot do this
  • Form field filling and reading
  • Digital signature creation and verification
  • PDF/A validation and conversion
  • Annotation read/write
  • Production-grade commercial support
  • pdf-rs is MIT licensed and free
  • pdf-rs parsing is well-tested for read-only scenarios
  • pdf-rs is actively maintained by the Rust community

pdf-rs (Rust)

  • Free and open source (MIT)
  • Pure Rust — same language, no FFI
  • Good for read-only PDF parsing use cases
  • Community-maintained with open issues/PRs
  • No write support — cannot save modified PDFs
  • No form field operations
  • No digital signatures
  • No PDF/A
  • Limited to parsing — not suitable for a production document workflow

When to use each

Choose PDFluent

Choose PDFluent if you need to write, modify, sign, or validate PDFs — not just read them. Any production document workflow (filling forms, signing, archiving) requires write capabilities that pdf-rs does not have.

Choose pdf-rs (Rust)

pdf-rs is fine for a read-only parser in an open source Rust project — extracting text from PDFs, reading metadata, or inspecting document structure without modification.

Bottom line

If you only need to read and parse PDF structure in a Rust project and do not need to write anything back, pdf-rs is a lightweight option. If your use case involves any write operation, form filling, signing, or validation, you need PDFluent.

Frequently asked questions

Can pdf-rs write or modify PDFs?
No. pdf-rs is a read-only parser. The crate has no write API and the maintainers have not indicated plans to add one.
Can pdf-rs fill AcroForm fields?
No. Form filling requires write access to the document structure. pdf-rs can read field definitions but cannot modify them.
Is pdf-rs production-ready?
pdf-rs handles many real-world PDFs but has known gaps with complex content streams and non-standard encodings. It is an active open-source project.
Does PDFluent replace pdf-rs as a dependency?
If you are using pdf-rs for read-only parsing, PDFluent can replace it while also giving you write, form, signing, and validation capabilities. Cargo dependency size increases but you gain a complete API.
SDK · Install

Try it on your own files.

Free under the AGPLv3, or a commercial licence if you would rather not publish your own source.