What is the difference between PDF/A and a normal PDF?

A normal PDF can rely on things outside the file, such as fonts installed on your computer, and can use passwords and scripts. PDF/A (ISO 19005) forbids those and requires embedded fonts and defined colour, so the file looks the same years later. Archives and some official systems ask for it.

What do PDF/A-1b, PDF/A-2b and PDF/A-2u mean?

The number is the part of the standard, each based on a different PDF version. The letter is the conformance level: b (basic) guarantees the appearance, u adds reliable Unicode text for searching and copying, and a adds a tagged structure for accessibility. PDF/A-4 no longer uses these letters.

Is PDF/X the same as a high-quality PDF?

No. A high-quality export preset only controls things like image resolution. PDF/X is a standard with fixed rules on fonts, colour, page boxes and output intent, so a printer can rely on it. Ask your printer which PDF/X version they want.

How do I check if my PDF is really PDF/A?

Acrobat Reader shows the claim in its Standards panel, but a claim is not proof. Run the file through a validator such as veraPDF, which is free and open source, to see whether it actually conforms.

Can I convert a PDF to PDF/A in Kopitiam?

No. Kopitiam doesn’t create or validate PDF/A or PDF/X, and its edits can remove or invalidate an existing PDF/A claim. Make your edits first, then convert the result with a tool that produces and checks PDF/A, or export again from the source document.

PDF/A vs PDF/X vs regular PDF: what’s the difference?

A regular PDF is for everyday viewing and sharing. PDF/A is a stricter subset of PDF made for long-term archiving: the file must carry everything it needs, such as its fonts, so it still opens and looks the same years from now. PDF/X is a stricter subset made for professional printing, with rules about colour, fonts and page boxes so a print shop gets predictable output.

All three use the same .pdf extension and open in the same readers. The difference is the promise the file makes. If nobody has asked you for PDF/A or PDF/X, a regular PDF is the right choice and you don’t need to change anything.

What a regular PDF is, and why it is usually enough

A regular PDF can use almost any feature the format allows: fonts that are not embedded, links to outside content, scripts, passwords, video and fillable forms. That flexibility is why it works for payslips, tenancy agreements, CVs and boarding passes.

The cost is that nothing is guaranteed. A file that relies on a font installed on the sender’s computer can look different on yours. For a document you read this week, that rarely matters. For a record someone must open in 20 years, or a brochure going to press, it can.

PDF/A: built for archiving

PDF/A is the ISO 19005 standard. Its core rule is that the file is self-contained and its appearance can be reproduced without anything outside the file. In practice that means:

Every font used is embedded in the file.
Colour is defined in a device-independent way, usually with an embedded colour profile.
No encryption or passwords.
No JavaScript, no audio or video, and no content that depends on an outside file or website.
Metadata is stored in a standard form (XMP), and that is also where the file declares that it is PDF/A.

The standard comes in parts, each built on a different version of PDF:

PDF/A-1 (2005), based on PDF 1.4. The strictest: transparency is not allowed.
PDF/A-2 (2011), based on PDF 1.7. Allows transparency, layers and JPEG 2000 images, and lets you embed other PDF/A files.
PDF/A-3 (2012). Like PDF/A-2, but you can attach files of any type. Electronic invoice formats such as Factur-X and ZUGFeRD use this to carry machine-readable invoice data inside a readable PDF.
PDF/A-4 (2020), based on PDF 2.0. It drops the old conformance letters and has variants such as PDF/A-4f for files with attachments.

In parts 1 to 3, a letter after the number says how strict the file is. Level B (basic) guarantees the pages look right. Level U adds reliable Unicode text, so you can search and copy it; it exists in PDF/A-2 and PDF/A-3. Level A (accessible) also requires a tagged structure, such as headings and reading order, for screen readers. So PDF/A-2b means part 2, level B.

PDF/X: built for printing

PDF/X is the ISO 15930 family, made so a file prints the same way on any compliant press. Every version requires embedded fonts, no encryption, a defined trim box (or art box) for the finished page size, and an output intent that names the printing conditions the colours were prepared for.

PDF/X-1a: CMYK and spot colours only, no transparency. The old safe default many printers still accept.
PDF/X-3: also allows colour-managed RGB and Lab colour.
PDF/X-4: allows live transparency and layers. A common modern choice for design apps.
PDF/X-6: the version based on PDF 2.0.

Bleed is a separate question. If your design runs to the edge of the page, the printer needs extra image beyond the trim line, and they will tell you how much. A PDF/X file can record that with a bleed box, but the standard does not add bleed for you.

Side by side

Purpose: regular PDF is for sharing and reading; PDF/A is for keeping; PDF/X is for printing.
Fonts: optional in a regular PDF; must be embedded in both PDF/A and PDF/X.
Passwords: allowed in a regular PDF; not allowed in PDF/A or PDF/X.
Colour: anything goes in a regular PDF; PDF/A needs device-independent colour; PDF/X targets a named print condition.
Forms and scripts: fine in a regular PDF; PDF/A bans scripts and restricts interactive features.
Who asks for it: nobody, for a regular PDF; archives, records offices and some e-filing or e-invoicing systems for PDF/A; print shops for PDF/X.

How to tell which one you have

Open the file in Adobe Acrobat or Acrobat Reader. A file that claims PDF/A usually opens with a notice bar about the standard, and the Standards panel shows the part and level.
In other readers, look in Document Properties. Some show the PDF/A or PDF/X claim, many do not.
For a definite answer, run the file through a validator. veraPDF is a free, open-source PDF/A validator. For PDF/X, the preflight tools in professional print software, or your printer, can check it.

A PDF/A or PDF/X label is only a claim written into the file. Any app can write it, and editing the file afterwards can quietly make it untrue. If a records office or print shop will reject a file that fails, validate it, don’t trust the label.

How to make a PDF/A or PDF/X file

Make it from the source document when you can, not from an existing PDF. Converting a finished PDF often fails on missing fonts or unusual colour, and fixing that needs professional tools.

Microsoft Word: when saving as PDF, open the options and tick the PDF/A setting.
LibreOffice: use Export as PDF and choose the PDF/A option in the export dialog.
Design apps such as Adobe InDesign and Affinity Publisher: pick a PDF/X preset when exporting, and ask your printer which one they want.
Scanners and scanning apps: many offer PDF/A as an output format, which is useful for archiving paper records.

What happens if you edit one in Kopitiam

Kopitiam doesn’t create, convert to or check PDF/A or PDF/X. You can open these files, because they are PDFs, but treat what you download as a regular PDF.

Edit PDF, Merge, Split, Extract pages, Organise and Redact build a new file from your pages. The new file doesn’t carry the original’s XMP metadata, which is where the PDF/A claim lives, so it no longer declares PDF/A at all.
Rotate, Watermark and Add page numbers save changes into the same file. The PDF/A claim stays, but the document information is updated (producer and modified date) without updating the matching XMP, and that mismatch can break conformance.
When you add Latin-script text with the editor, watermark or page numbers, Kopitiam uses a standard built-in PDF font that isn’t embedded in the file. PDF/A and PDF/X both require embedded fonts.

So if you must hand in PDF/A or PDF/X, do your Kopitiam edits first, then convert the result with a tool that produces and checks the standard. Or make your changes in the source document and export again.

Which one should you use?

Emailing a signed tenancy agreement, sending a payslip or uploading a CV: a regular PDF.
Scanning old land documents or company records to keep: PDF/A, if your scanner or archive supports it.
A portal that says PDF/A is required: ask which part and level they accept, then validate before you upload.
A banner, flyer or packaging going to a print shop: PDF/X, in the version your printer names.

The PDF tools on Kopitiam that change files (edit, merge, split, organise, compress, redact and the rest) run in your browser, so your file isn’t uploaded to a server while you work on it.