Add your XLF file
Drop one or more .xlf files onto the converter above, or browse for them. They load into browser memory only — nothing is uploaded, so there is no size-based pricing and no server queue.
Converting a .xlf font to .arb repackages the same glyphs and metrics for a different delivery target. Free, private, and validated — the file never leaves your browser.
Batch files can each use a different output. Nothing uploads for local conversions.
Working inputs include camera RAW, browser-local audio/video, PDF, CBZ/CBR comics, office documents, ebooks, markup, 3D models, structured text, images, and archives.Converting a .xlf font to .arb repackages the same glyphs and metrics for a different delivery target. A .xlf file is an XLIFF document — the OASIS XML standard for moving translation work between tools. Each translatable string becomes a trans-unit holding a source element and, once translated, a target element, wrapped in a file element that records the source and target languages.
An .arb file is an Application Resource Bundle: a JSON object in which each key maps to a translatable string, and keys prefixed with @ carry that string's metadata — its description, its placeholder types and their formatting. It is the localisation format Flutter's intl tooling generates from and compiles to typed Dart accessors. For this route the practical draw is metadata lives with the string, so translators get context without a separate file and iCU MessageFormat covers plurals and gender without extra entries — balanced against the @-key convention doubles the entry count and looks odd to anyone new to it, which is worth knowing before you commit a large batch.
The practical trigger for this conversion is usually a mismatch: with .xlf, verbose — several lines of markup per string. Switching to .arb buys you metadata lives with the string, so translators get context without a separate file, which is why it is the better fit for localising a Flutter application through gen_l10n. Because the conversion runs locally, trying it costs nothing but a few seconds of compute on your own machine.
| Aspect | XLIFF 1.2 (.xlf) | Application Resource Bundle (.arb) |
|---|---|---|
| Format type | Text-based — characters and structure, so there is no visual quality loss | Text-based — characters and structure, so there is no visual quality loss |
| How it stores data | the root xliff element declares a version; file elements carry source-language and target-language attributes | the document is a single JSON object; ordinary keys map to strings, and @-prefixed keys map to metadata objects for the key of the same name |
| Strongest at | sending strings to a translation agency and getting reviewed work back | localising a Flutter application through gen_l10n |
| Weak spot | verbose — several lines of markup per string | the @-key convention doubles the entry count and looks odd to anyone new to it |
| Metadata | unit identifiers, source and target text and the declared source/target languages are preserved. Translation state, notes and inline placeholder markup are not carried into flat key-value formats, which have nowhere to record them | keys and their translated values are preserved. @-prefixed metadata — descriptions, placeholder types and formats — and the @@locale marker are skipped rather than converted, because flat key-value targets have nowhere to put them |
Drop one or more .xlf files onto the converter above, or browse for them. They load into browser memory only — nothing is uploaded, so there is no size-based pricing and no server queue.
Select .arb in the output menu next to each file. The menu only offers targets this engine can genuinely produce, so if ARB is selectable, the route is real and validated.
Press Convert. The font tables are parsed and rewritten locally with fonteditor-core; glyph outlines, hinting, and kerning survive the trip.
Each result is signature-checked before the download unlocks, so a failed encode can never masquerade as a valid ARB file. Outputs keep the original filename with the .arb extension.
There is no visual quality to lose — xlf is text-oriented and arb is text-oriented, so the question is structural fidelity. Text, ordering, and basic structure are preserved; complex layout, embedded objects, and styling beyond the target's model are simplified.
Yes — the .xlf file is processed inside your browser tab and never uploaded. The font tables are parsed and rewritten locally with fonteditor-core; glyph outlines, hinting, and kerning survive the trip. Close the tab and the file is gone from memory.
Flutter's tooling reads ARB natively and the major translation platforms support it; elsewhere it is just JSON. Novus Convert flattens the bundle locally, skipping @-prefixed metadata keys so they do not appear as translatable entries, and converts to and from the other localization formats. Placeholder metadata and ICU plural structure are not representable in flat targets.
It depends on the content: the document is a single JSON object; ordinary keys map to strings, and @-prefixed keys map to metadata objects for the key of the same name. Convert one representative file first and compare before batch-processing a large set.
In .xlf, unit identifiers, source and target text and the declared source/target languages are preserved. Translation state, notes and inline placeholder markup are not carried into flat key-value formats, which have nowhere to record them. Re-encoding through the browser pipeline does not carry embedded metadata into the output, which doubles as a privacy scrub — check the exported file if you specifically need tags preserved.
Yes — the reverse route exists as a separate tool. Bear in mind that round-tripping .xlf → .arb → .xlf is not a perfect undo when any lossy step is involved; keep your original if fidelity matters.