Translate SDLXLIFF files online. Tags intact. TM respected.
Drop your .sdlxliff and get it back ready to open in Trados Studio — fully translated, with inline tags preserved and your TM 100/101 matches never touched.
What is Trados SDLXLIFF?
SDLXLIFF is the native bilingual format of Trados Studio, the most widely used CAT tool in the translation industry. It's an XML-based file that pairs source and target segments, carries inline formatting tags (<g>, <x>, <bpt>, <ept>), and stores translation memory metadata such as match scores (100%, 101% in-context matches, fuzzy bands) and locked translation units.
Translators receive SDLXLIFF files from project managers, translate them in Trados Studio or compatible CAT tools, and return them with the target column filled in. The challenge is that any malformed tag, missing xid attribute, or modified locked segment breaks the file on return — Trados rejects it with errors like "Missing locked content for Oasis.Xliff12.x".
Why Trados SDLXLIFF is tricky for AI translation
- Inline tags (<g id="1">, <x id="2"/>) must appear in the target with the same IDs and the same nesting. AI models routinely drop, duplicate, or renumber them.
- Locked translation units carry xid attributes that must match across source and target. Cloning them naively creates orphan references that Trados rejects.
- TM 100/101 matches lose their match status if any byte changes — even a normalized quote or different whitespace. AI tools that "improve" pre-translated segments destroy the match score.
- mid and xid attribute order matters for some Trados versions. Reordering attributes during XML rewrite breaks tag equivalence checks.
- Phase 6 tag validation in reassemble: if the target doesn't exactly mirror the source's tag structure, the file is invalid.
How Fily handles Trados SDLXLIFF
- Tag preservation: each <g>, <x>, <bpt>, <ept> is extracted with its full attribute set before translation, the segment is translated as text with indexed placeholders, then tags are reinserted in their original positions with original IDs.
- Locked TU handling: locked segments with matching xid overlap are smart-cloned; isolated locked segments are passed through untouched.
- TM 100/101 pass-through: any segment marked as 100% or 101% match in the original is never sent to the model. It's copied byte-for-byte to the target.
- xid normalization: the reassemble step strips id= and xid= differences during validation to allow legitimate renumbering without breaking equivalence checks.
- 12-step QA: glossary enforcement, consistency checks, forbidden-term replacement, tag count repair, and 8 other passes — all auditable in the QA report HTML attached to your delivery.
Pipeline: sdlxliff_trados@2.0.0
The Trados SDLXLIFF workflow with Fily
Upload
Drop your .sdlxliff (single or batch ZIP). Optional: glossary, TM, style guide.
Process
Fily runs the Trados SDLXLIFF pipeline + 12 QA steps. Typical job: 10–20 minutes.
Download
Same format, ready to deliver. QA report HTML attached.
Most teams use Fily for first-pass translation of bulk SDLXLIFF batches before assigning them to in-house reviewers. Reviewers open the file in Trados as usual — segments are pre-translated, tags are intact, locked TUs untouched — and focus only on segments flagged in the QA report.
Beyond the standard pipeline
What we've built around Trados SDLXLIFF
Edge cases clients brought us for this format — and the pipelines we shipped to solve them.
4-layer cascade
Multi-tenant glossary cascade
An LSP with 40+ end-clients needed org-level terms, client-level overrides, and sub-client (brand) overrides to all stack — without re-attaching glossaries to every job.
A 4-layer cascade: system → org → client → sub-client → job. Forbidden terms inherit and override, style guides cascade, and every future job picks up the right rules automatically.
Golden TM · auto-build
A translation memory that builds itself
Clients wanted TM leverage but didn't want to maintain a TM — exporting, cleaning and re-importing TMX after every project is a job nobody has time for.
Every confirmed segment is promoted into the organization's Golden TM automatically, scoped per client and language pair, and reused on every future job. Reviewer edits in the dashboard feed straight back in. Exact matches then cost $0.
cross-file consistency
One term, one translation, across the batch
In a 50-file client project, the same English sentence would come back translated two or three different ways across files — and reviewers had to catch it manually, file by file.
A tag-safe consistency pass runs across the entire batch, flags every source span with divergent targets, and unifies them in one click from the review editor — without touching inline tags.
GS-TXLF count parity
Word counts that match your CAT tool exactly
An LSP reconciled Fily's word count against their Trados/GroupShare analysis and the numbers didn't line up — pre-translated and locked segments were being counted differently, breaking the billing conversation.
The count is read from the CAT file's own analysis: match categories are frozen from the file, 100%/101%/ICE/locked come through free, and internal repetitions are detected the way the CAT tool sees them. Analyses now reconcile to the segment.
Frequently asked about Trados SDLXLIFF
Other formats Fily translates
Ready to translate a Trados SDLXLIFF file?
No card. No setup. Upload one file and see the output.