{"course":{"slug":"vector-and-print","title":"Vectors, Logos and Things That Get Printed","url":"https://addaly.com/learn/vector-and-print","level":"beginner","track":"create"},"lesson":{"slug":"pdf-x-flavours","title":"PDF/X, and what each flavour forbids","url":"https://addaly.com/learn/vector-and-print/pdf-x-flavours","position":57,"of":73,"minutes":8,"answer":"Every PDF/X flavour embeds fonts, defines a TrimBox and names an output intent, and they differ in what they allow: X-1a forbids RGB and flattens transparency.","keyIdea":"Every PDF/X flavour embeds fonts, defines a TrimBox and names an output intent, and they differ in what they allow: X-1a forbids RGB and flattens transparency, X-4 keeps transparency live for the RIP to flatten once at device resolution."},"body":{"format":"markdown","text":"## PDF/X is a PDF with the dangerous parts removed\n\nAn ordinary PDF can contain RGB images, missing fonts, JavaScript, video, layers, comments, form fields and an unstated colour intent. A press cannot do anything sensible with most of that.\n\n**PDF/X** is a family of ISO standards defining subsets suitable for exchange. Every flavour requires:\n\n- All fonts embedded.\n- No JavaScript, no video, no form fields, no encryption.\n- A **TrimBox or ArtBox** defined, so the finished size is unambiguous.\n- An **output intent**: a named characterisation of the intended printing condition, such as `FOGRA39` or `Japan Color 2001 Coated`.\n\nThe last one is the point of the standard. A PDF/X file says what printing condition its colours were prepared for. A plain PDF does not, and everything else is guesswork.\n\n## The flavours you will meet\n\n**PDF/X-1a:2001 and :2003.** The conservative one. Everything must be CMYK or spot (**no RGB at all**) and **all transparency is flattened** before export. No live transparency, no colour management inside the file beyond the output intent. Still the default request at a large number of shops, because it cannot surprise their RIP.\n\n**PDF/X-3:2002/2003.** Permits colour-managed data (RGB and Lab with embedded profiles) leaving conversion to the RIP. Transparency still flattened. Used mostly in Europe, and Scribus's default export target.\n\n**PDF/X-4:2010.** Permits **live transparency and layers**, and colour-managed content. The RIP flattens once, at device resolution, with full knowledge. This is the better standard where the shop's RIP supports it: no atomic regions in your file, no hairline seams, smaller files.\n\n**PDF/X-5 and PDF/X-6.** X-5 adds external references (a file that points at another file), rarely used in general commercial work. X-6 (2020) is the modern successor built on PDF 2.0. Neither is what a local shop will ask for.\n\n> Figure: What each PDF/X flavour forbids. Timeline: 2001, PDF/X-1a. CMYK and spot only, no RGB at all, and every piece of transparency flattened before it leaves your machine; 2002, PDF/X-3. Colour-managed RGB and Lab allowed, with conversion left to the RIP. Transparency still flattened; 2010, PDF/X-4. Live transparency and layers. The RIP flattens once, at device resolution, knowing the device; 2020, PDF/X-6, built on PDF 2.0. Correct, modern, and not what a local shop is going to ask you for. Every one of them embeds the fonts, defines a TrimBox and names an output intent. They differ only in what they allow through, so the question to the shop is two words long: X-1a or X-4?\n\n## Choosing, in two questions\n\n1. **\"Do you want X-1a or X-4?\"** Ask. If they say X-1a, send X-1a. If they say \"either\", send X-4 for anything with transparency and X-1a for flat line work.\n2. **\"Which output intent?\"** Their answer names the profile you convert to. If they cannot say, ISO Coated v2 (FOGRA39) for coated European-style work and Japan Color 2001 Coated for a great deal of Asian work are defensible defaults, but the question is better than the default.\n\n## Exporting it\n\n- **InDesign / Illustrator**: File ▸ Export ▸ Adobe PDF (Print), then the `[PDF/X-1a:2001]` or `[PDF/X-4:2008]` preset. Marks and Bleeds ▸ *Use Document Bleed Settings* and *Crop Marks* with a 3 mm offset. Output ▸ set the destination and the output intent profile.\n- **CorelDRAW**: File ▸ Publish to PDF ▸ Settings ▸ the PDF/X-1a or PDF/X-4 preset; bleed and crop marks on the Prepress tab.\n- **Scribus**: File ▸ Export ▸ Save as PDF. Choose PDF/X-1a, X-3 or X-4 in the General tab's compatibility dropdown, set bleed on Pre-Press, and **set the output intent profile on the Colour tab**: Scribus will refuse to export a PDF/X file without one, which is the standard being enforced correctly.\n- **Affinity Publisher**: File ▸ Export ▸ PDF, with the PDF/X presets in the preset list.\n\n## Where the shop's answer comes from\n\nA shop that says \"X-1a only\" is usually running an older RIP, or has been burned by a transparency job and does not want the argument. Neither is unreasonable. A shop that says \"X-4 preferred\" has a modern workflow and is telling you they would rather flatten it themselves, correctly, than receive somebody's pre-flattened approximation.\n\nIf you have a choice and the job has soft shadows, transparency or placed PSDs, X-4 is materially better and the file will be smaller. If the job is flat line work with spot colours, the flavour makes almost no difference and X-1a is one less thing to discuss.\n\n## Verifying you got what you asked for\n\nNever trust the preset name. Check the file:\n\n```bash\npdfinfo job.pdf | grep -i -E 'page size|pdf version'\npdffonts job.pdf\n```\n\nFor the X-conformance claim itself, Acrobat Pro's Preflight has PDF/X profiles, and the free **veraPDF** validator, though aimed primarily at PDF/A, also validates PDF/X conformance levels. Ghostscript will tell you about structure but not about conformance.\n\n## The limitation\n\nA file can be technically valid PDF/X and still be wrong for the job: correct structure, wrong output intent, images at 90 ppi, artwork 4 mm off the trim. **Conformance is a floor, not a check on your work.** The standard guarantees the press can process the file. Everything about whether the file is *right* is the next three lessons."},"check":{"question":"A job containing several soft drop shadows is exported as PDF/X-1a because the shop's preset list offered it first. What is the most significant consequence of that choice?","options":[{"text":"The output intent is omitted, since X-1a defines colour purely by device values rather than by any printing characterisation.","correct":false,"tempting":"Every PDF/X flavour requires an output intent, including X-1a; it is one of the defining requirements of the family."},{"text":"Fonts will be embedded as full sets rather than subsets, increasing the file size substantially.","correct":false,"tempting":"Subsetting is an export setting unrelated to the X flavour; X-1a neither requires nor forbids full embedding."},{"text":"Layers are preserved, so the shop can switch the shadows off if the RIP struggles with them.","correct":false,"tempting":"X-1a forbids optional content layers; X-4 is the flavour that permits them, and a shop cannot switch off flattened artwork in any case."},{"text":"Transparency is flattened on export, splitting the page into atomic regions where seams can appear.","correct":true}]},"prev":{"slug":"what-a-rip-does","title":"What a RIP actually does with your file","url":"https://addaly.com/learn/vector-and-print/what-a-rip-does"},"next":{"slug":"the-five-pdf-boxes","title":"The five rectangles inside a PDF","url":"https://addaly.com/learn/vector-and-print/the-five-pdf-boxes"},"authorship":"Founder and series editor: Dr Mustafa Mun. Written by AI models to a written standard. Exam keys checked blind by a second model: 3,665 of 3,666 agreed. Academic review invited.","review":{"status":"Draft, open for academic review"},"cite":"Addaly (2026) 'PDF/X, and what each flavour forbids', in Vectors, Logos and Things That Get Printed. Edited by M. Mun. Addaly. Available at: https://addaly.com/learn/vector-and-print/pdf-x-flavours (Accessed: 13 October 2026).","licence":{"name":"CC BY-NC-SA 4.0","url":"https://creativecommons.org/licenses/by-nc-sa/4.0/"},"reader":{"schema":1,"title":"PDF/X, and what each flavour forbids","courseTitle":"Vectors, Logos and Things That Get Printed","module":{"index":7,"slug":"the-handover","title":"The handover"},"answer":null,"keyIdea":"Every PDF/X flavour embeds fonts, defines a TrimBox and names an output intent, and they differ in what they allow: X-1a forbids RGB and flattens transparency, X-4 keeps transparency live for the RIP to flatten once at device resolution.","hero":{"kind":"figure","figure":{"t":"figure","label":"Figure","figure":{"type":"timeline","title":"What each PDF/X flavour forbids","events":[{"when":"2001","what":"PDF/X-1a. CMYK and spot only, no RGB at all, and every piece of transparency flattened before it leaves your machine"},{"when":"2002","what":"PDF/X-3. Colour-managed RGB and Lab allowed, with conversion left to the RIP. Transparency still flattened"},{"when":"2010","what":"PDF/X-4. Live transparency and layers. The RIP flattens once, at device resolution, knowing the device"},{"when":"2020","what":"PDF/X-6, built on PDF 2.0. Correct, modern, and not what a local shop is going to ask you for"}],"caption":"Every one of them embeds the fonts, defines a TrimBox and names an output intent. They differ only in what they allow through, so the question to the shop is two words long: X-1a or X-4?"},"alt":"Figure: What each PDF/X flavour forbids. Timeline: 2001, PDF/X-1a. CMYK and spot only, no RGB at all, and every piece of transparency flattened before it leaves your machine; 2002, PDF/X-3. Colour-managed RGB and Lab allowed, with conversion left to the RIP. Transparency still flattened; 2010, PDF/X-4. Live transparency and layers. The RIP flattens once, at device resolution, knowing the device; 2020, PDF/X-6, built on PDF 2.0. Correct, modern, and not what a local shop is going to ask you for. Every one of them embeds the fonts, defines a TrimBox and names an output intent. They differ only in what they allow through, so the question to the shop is two words long: X-1a or X-4?"}},"blocks":[{"t":"h2","id":"pdf-x-is-a-pdf-with-the-dangerous-parts-removed","runs":[{"text":"PDF/X is a PDF with the dangerous parts removed"}]},{"t":"p","runs":[{"text":"An ordinary PDF can contain RGB images, missing fonts, JavaScript, video, layers, comments, form fields and an unstated colour intent. A press cannot do anything sensible with most of that."}]},{"t":"p","runs":[{"text":"PDF/X","b":true},{"text":" is a family of ISO standards defining subsets suitable for exchange. Every flavour requires:"}]},{"t":"ul","items":[[{"text":"All fonts embedded."}],[{"text":"No JavaScript, no video, no form fields, no encryption."}],[{"text":"A "},{"text":"TrimBox or ArtBox","b":true},{"text":" defined, so the finished size is unambiguous."}],[{"text":"An "},{"text":"output intent","b":true},{"text":": a named characterisation of the intended printing condition, such as "},{"text":"FOGRA39","code":true},{"text":" or "},{"text":"Japan Color 2001 Coated","code":true},{"text":"."}]]},{"t":"p","runs":[{"text":"The last one is the point of the standard. A PDF/X file says what printing condition its colours were prepared for. A plain PDF does not, and everything else is guesswork."}]},{"t":"h2","id":"the-flavours-you-will-meet","runs":[{"text":"The flavours you will meet"}]},{"t":"p","runs":[{"text":"PDF/X-1a:2001 and :2003.","b":true},{"text":" The conservative one. Everything must be CMYK or spot ("},{"text":"no RGB at all","b":true},{"text":") and "},{"text":"all transparency is flattened","b":true},{"text":" before export. No live transparency, no colour management inside the file beyond the output intent. Still the default request at a large number of shops, because it cannot surprise their RIP."}]},{"t":"p","runs":[{"text":"PDF/X-3:2002/2003.","b":true},{"text":" Permits colour-managed data (RGB and Lab with embedded profiles) leaving conversion to the RIP. Transparency still flattened. Used mostly in Europe, and Scribus’s default export target."}]},{"t":"p","runs":[{"text":"PDF/X-4:2010.","b":true},{"text":" Permits "},{"text":"live transparency and layers","b":true},{"text":", and colour-managed content. The RIP flattens once, at device resolution, with full knowledge. This is the better standard where the shop’s RIP supports it: no atomic regions in your file, no hairline seams, smaller files."}]},{"t":"p","runs":[{"text":"PDF/X-5 and PDF/X-6.","b":true},{"text":" X-5 adds external references (a file that points at another file), rarely used in general commercial work. X-6 (2020) is the modern successor built on PDF 2.0. Neither is what a local shop will ask for."}]},{"t":"h2","id":"choosing-in-two-questions","runs":[{"text":"Choosing, in two questions"}]},{"t":"ol","start":1,"items":[[{"text":"”Do you want X-1a or X-4?”","b":true},{"text":" Ask. If they say X-1a, send X-1a. If they say “either”, send X-4 for anything with transparency and X-1a for flat line work."}],[{"text":"”Which output intent?”","b":true},{"text":" Their answer names the profile you convert to. If they cannot say, ISO Coated v2 (FOGRA39) for coated European-style work and Japan Color 2001 Coated for a great deal of Asian work are defensible defaults, but the question is better than the default."}]]},{"t":"h2","id":"exporting-it","runs":[{"text":"Exporting it"}]},{"t":"ul","items":[[{"text":"InDesign / Illustrator","b":true},{"text":": File ▸ Export ▸ Adobe PDF (Print), then the "},{"text":"[PDF/X-1a:2001]","code":true},{"text":" or "},{"text":"[PDF/X-4:2008]","code":true},{"text":" preset. Marks and Bleeds ▸ "},{"text":"Use Document Bleed Settings","i":true},{"text":" and "},{"text":"Crop Marks","i":true},{"text":" with a 3 mm offset. Output ▸ set the destination and the output intent profile."}],[{"text":"CorelDRAW","b":true},{"text":": File ▸ Publish to PDF ▸ Settings ▸ the PDF/X-1a or PDF/X-4 preset; bleed and crop marks on the Prepress tab."}],[{"text":"Scribus","b":true},{"text":": File ▸ Export ▸ Save as PDF. Choose PDF/X-1a, X-3 or X-4 in the General tab’s compatibility dropdown, set bleed on Pre-Press, and "},{"text":"set the output intent profile on the Colour tab","b":true},{"text":": Scribus will refuse to export a PDF/X file without one, which is the standard being enforced correctly."}],[{"text":"Affinity Publisher","b":true},{"text":": File ▸ Export ▸ PDF, with the PDF/X presets in the preset list."}]]},{"t":"h2","id":"where-the-shop-s-answer-comes-from","runs":[{"text":"Where the shop’s answer comes from"}]},{"t":"p","runs":[{"text":"A shop that says “X-1a only” is usually running an older RIP, or has been burned by a transparency job and does not want the argument. Neither is unreasonable. A shop that says “X-4 preferred” has a modern workflow and is telling you they would rather flatten it themselves, correctly, than receive somebody’s pre-flattened approximation."}]},{"t":"p","runs":[{"text":"If you have a choice and the job has soft shadows, transparency or placed PSDs, X-4 is materially better and the file will be smaller. If the job is flat line work with spot colours, the flavour makes almost no difference and X-1a is one less thing to discuss."}]},{"t":"h2","id":"verifying-you-got-what-you-asked-for","runs":[{"text":"Verifying you got what you asked for"}]},{"t":"p","runs":[{"text":"Never trust the preset name. Check the file:"}]},{"t":"code","lang":"bash","label":"Bash","text":"pdfinfo job.pdf | grep -i -E 'page size|pdf version'\npdffonts job.pdf"},{"t":"p","runs":[{"text":"For the X-conformance claim itself, Acrobat Pro’s Preflight has PDF/X profiles, and the free "},{"text":"veraPDF","b":true},{"text":" validator, though aimed primarily at PDF/A, also validates PDF/X conformance levels. Ghostscript will tell you about structure but not about conformance."}]},{"t":"h2","id":"the-limitation","runs":[{"text":"The limitation"}],"role":"limit"},{"t":"p","runs":[{"text":"A file can be technically valid PDF/X and still be wrong for the job: correct structure, wrong output intent, images at 90 ppi, artwork 4 mm off the trim. "},{"text":"Conformance is a floor, not a check on your work.","b":true},{"text":" The standard guarantees the press can process the file. Everything about whether the file is "},{"text":"right","i":true},{"text":" is the next three lessons."}]}],"check":{"question":[{"text":"A job containing several soft drop shadows is exported as PDF/X-1a because the shop’s preset list offered it first. What is the most significant consequence of that choice?"}],"options":[{"text":[{"text":"The output intent is omitted, since X-1a defines colour purely by device values rather than by any printing characterisation."}],"correct":false,"tempting":[{"text":"Every PDF/X flavour requires an output intent, including X-1a; it is one of the defining requirements of the family."}]},{"text":[{"text":"Fonts will be embedded as full sets rather than subsets, increasing the file size substantially."}],"correct":false,"tempting":[{"text":"Subsetting is an export setting unrelated to the X flavour; X-1a neither requires nor forbids full embedding."}]},{"text":[{"text":"Layers are preserved, so the shop can switch the shadows off if the RIP struggles with them."}],"correct":false,"tempting":[{"text":"X-1a forbids optional content layers; X-4 is the flavour that permits them, and a shop cannot switch off flattened artwork in any case."}]},{"text":[{"text":"Transparency is flattened on export, splitting the page into atomic regions where seams can appear."}],"correct":true,"tempting":null}],"order":[0,1,3,2],"why":null},"prev":{"slug":"what-a-rip-does","title":"What a RIP actually does with your file","minutes":8},"next":{"slug":"the-five-pdf-boxes","title":"The five rectangles inside a PDF","minutes":8}}}