Supported file formats

Overview

Smartcat supports a wide variety of file formats for translation and localization. When you upload a file, Smartcat detects the format automatically and routes it to the appropriate processing engine.

Drag and drop your files or select them when creating a new project or translation task. If a file format is not supported, an error message appears and the file is not uploaded.

Supported file formats

Microsoft Office

• DOC / DOCX

• XLS / XLSX / XLSM

• PPT / PPTX / PPS / PPSX / POT / POTX

📌 Microsoft Office formats are proprietary and complex. Some post-processing may be required on translated documents.

Open Office

• ODT

• ODP

Text and rich text

• TXT

• RTF

Data and Spreadsheets

• CSV

Markdown

• MD / MKD / MDWN / MDOWN / MDTXT / MDTEXT / MARKDOWN

Hypertext

• HTML / HTM

• PHP

Bilingual interchange formats

• XLIFF (XLF) 1.2 and 2.0

• SDLXLIFF

• MQXLIFF

• XLIFF files from Articulate Rise 360

• XLIFF files from Articulate Storyline

• XLIFF files from Easygenerator

• PO / POT

• TTX

Desktop publishing

• PDF

• IDML (Adobe InDesign)

• INX

• MIF (FrameMaker)

📌 PDF files are processed using OCR. See the Images (OCR) section for supported input formats.

Technical writing

• DITA XML

• DITAMAP

• HELP+MANUAL XML

Localization

• XML

• TTML

• Android XML

• RESX

• LOCJSON

• JSON

• TJSON

• YML / YAML

• INC

• INX

• STRINGS (Apple)

• STRINGSDICT (Apple)

• XCSTRINGS (Apple Xcode string catalog)

• PROPERTIES (Java)

Learning content

• Articulate Rise SCORM course (ZIP)

• Articulate Storyline course (ZIP)

• Articulate Storyline native file (STORY)

Video

• MP4

• MPEG / MPG / M2V

• AVI

• MOV / QT

• MKV

• M4V

• FLV

• 3GP / 3G2

• OGV

• TS

• WMV

• VOB

Audio

• MP3

• MP2 / M2A

• M4A

• AAC

• OGG

• FLAC

• WMA

Subtitle

• SRT

• VTT

Images (OCR)

The following image and document formats are supported via OCR processing:

• JPG / JPEG / JFIF

• TIF / TIFF

• PNG

• BMP

• GIF

• DCX / PCX

• JP2 / JPC

• DJVU / DJV

• JB2

• PDF (image-only)

• AI (Adobe Illustrator)

Packages

• SDLPPX / SDLRPX

• WSXZ

• ZIP

📌 ZIP packages are used for IDML, DITA, Articulate Rise SCORM, Articulate Storyline courses, and other packaged content. Smartcat detects the package type automatically.

Unsupported formats

• FM (FrameMaker binary)

Blocked file extensions

To protect against security risks, Smartcat blocks upload of files with the following extensions. These cannot be uploaded regardless of content:

ade, adp, apk, app, appx, appxbundle, asp, aspx, asx, bas, bat, cab, cer, chm, cmd, cnt, com, cpl, crt, csh, der, diagcab, dll, dmg, exe, fxp, gadget, grp, hlp, hpj, hta, htc, inf, ins, iso, isp, its, jar, jnlp, js, jse, ksh, lib, lnk, mad, maf, mag, mam, maq, mar, mas, mat, mau, mav, maw, mcf, mda, mdb, mde, mdt, mdw, mdz, msc, msh, msh1, msh1xml, msh2, msh2xml, mshxml, msi, msix, msixbundle, msp, mst, msu, nsh, ops, osd, pcd, pif, pl, plg, prf, prg, printerexport, ps1, ps1xml, ps2, ps2xml, psc1, psc2, psd1, psdm1, pst, py, pyc, pyo, pyw, pyz, pyzw, reg, scf, scr, sct, sh, shb, shs, sys, theme, tmp, url, vb, vbe, vbp, vbs, vhd, vhdx, vsmacros, vsw, vxd, webpnp, website, ws, wsc, wsf, wsh, xbap, xll, xnk

⚠️ Note: js appears in the blocked extensions list above. If you need to translate JavaScript localization files, export them as JSON or another supported localization format.

Format-specific limitations and best practices

This section addresses common questions about specific file format handling.

Microsoft Office files

PowerPoint speaker notes

Speaker notes in PPTX files are not translated by default. To include them, enable the Upload notes (also shown as "Load notes") option in the file's advanced upload settings before adding it to a project:

1. In a project, click Upload → Upload documents

2. Upload your PPTX file

3. In the file settings, enable Load notes to translate speaker notes

   

4. Click Finish to finish the upload. You can also click Save Defaults to save your settings for the next PPTX file upload.

If notes are left unchecked, they are silently excluded from both translation and the word count, which can be easy to miss until a review catches it

PDF files

📌 For best results with scanned PDFs, ensure the source document has clear, high-resolution text.

E-Learning formats

Localization formats

Desktop publishing

📌 For IDML files, review the tag settings before translation to optimize segment handling. See: https://help.smartcat.com/idml-file-tag-settings/

FAQ — Format-specific questions

Q: Can Smartcat handle bilingual DOCX files with parallel columns?

A: Smartcat can export bilingual DOCX files with parallel source/target columns. However, importing edited bilingual DOCX files back into Smartcat is not currently supported.

Q: Do we support JSON Objects (nested structures)?

A: Yes, JSON files with nested object structures are supported. Ensure your JSON is properly formatted with standard key-value pairs.

Q: What happens with scanned PDFs in the PDF Agent?

A: Scanned PDFs are automatically processed using OCR (Optical Character Recognition) to extract text for translation. For best results, use high-resolution scans with clear text.

Q: Can we translate IDML files without quality degradation?

A: Yes, IDML files preserve original formatting. Use the IDML tag settings to optimize segment handling and simplify text formatting.

Q: Do we support xAPI (not just SCORM)?

A: xAPI (Tin Can) is not currently supported. SCORM 1.2 and SCORM 2004 (all editions) are fully supported.

Q: Can we handle Articulate Storyline audio files?

A: Articulate Storyline native support is on the short-term roadmap. Currently, you can export Storyline content as XLIFF for translation.