Rank by

Note: Many models do not disclose their training data. Some models may have been trained on one or more of the evaluation datasets, in which case their scores are not directly comparable to models that have not.

Rank by
Metric

Performance vs. Model Size

Test sets

ColumnDatasetSplitDomain
CoRal Conv. CoRal-project/coral-v3 — conversation testSpontaneous conversation
CoRal Read CoRal-project/coral-v3 — read_aloud testRead-aloud speech
CV17 (da) mozilla-foundation/common_voice_17_0 — da testCrowd-sourced read speech
FLEURS (da) google/fleurs — da_dk testRead speech
FTSpeech alexandrainst/ftspeech test_balancedParliamentary / broadcast

Methodology

Text normalisation

Applied identically to hypothesis and reference before scoring:

  1. Unicode NFKC — folds compatibility characters (ligatures, full-width digits, ²2) so visually equivalent forms match
  2. Danish number canonicalisation — separators inside a numeral are removed so formatting differences don't inflate WER. Thousands and decimals are both stripped: 1.2341234, and 3.14 / 3,14314
  3. Lowercase
  4. Strip punctuation — apostrophes inside a word (e.g. det's) are preserved; all other punctuation and symbols are removed
  5. Spelled-out numerals → digits — numbers written as words are folded to their digit form with text2num (otte og tredive and otteogtredive38; hundrede100), so spelling and spacing variants collapse onto one value before the expansion below. Bare en/et are left as indefinite articles
  6. Numerals → Danish words — standalone integers are spelled out with num2words (4fire, 24fireogtyve, 100ethundrede), so a model that writes "4" is not penalised against a reference that spells out "fire". Only clean standalone integers are converted; digits embedded in larger tokens (decades like 1960'erne, ranges) are left untouched
  7. Collapse whitespace

This is broadly consistent with the HF Open ASR Leaderboard (BasicTextNormalizer) and matches the de-facto Danish standard set by danish-speech-eval, whose "normalised WER" likewise spells numerals out as words.

Note: folding digit↔word formatting is a fairness correction, not a leniency — it is applied symmetrically to reference and hypothesis, so genuine number-recognition errors are still counted.
Note: Danish hesitation fillers (øh, hmm, …) are not removed in the published scores (the eval harness supports it as an opt-in, but it is off by default).
Note: Danish orthographic variants (aaå, oeø, aeæ) are not normalised — the digraphs occur legitimately as letter sequences (ekstraarbejde, place names like Aarhus), so a blind substitution would introduce errors. Different Unicode encodings of the same letter are unified by NFC.

Metric

WER (Word Error Rate, %) and CER (Character Error Rate, %) — lower is better.

WER = (substitutions + deletions + insertions) / reference_words × 100

CER = (char substitutions + deletions + insertions) / reference_chars × 100

Mean WER and Mean CER are macro-averages across all five test sets (equally weighted).

WER can exceed 100 %. The denominator is the reference word count, but the numerator counts insertions without a ceiling — if a model hallucinates or loops, it can emit far more words than the reference contains, pushing WER well above 100 %. This is mathematically correct and a real signal: scores above 100 % on a given dataset indicate the model is not usable for that domain.

Speed

Speed (x) = total audio duration / total inference time. A value of 30x means 30 seconds of audio processed per wall-clock second. Only the transcription call is timed — model load time is excluded. Measured on an NVIDIA A100 (80 GB).

Speed reflects the serving stack, not just the model. Some models are run through high-throughput engines such as vLLM (continuous batching, paged KV cache), which can be several times faster than a plain transformers generation loop for the same weights. Treat Speed as "best-effort real-world throughput on this GPU" rather than an intrinsic model property — it is not comparable across different serving stacks or hardware, and API models are network-bound.
No warm-up run. Timing starts on the first batch, so one-off costs (CUDA lazy init, kernel autotuning, graph capture) are folded into the measurement. This slightly understates throughput, more so on smaller test sets where the fixed overhead is less amortised.

Code & data

Results dataset: RyeAI/danish-asr-leaderboard
Eval code: github.com/Rye-A1/danish-asr-leaderboard

Adding a model

There are two paths, depending on whether you've run the evaluation yourself:

Request a model — we run it

If you can't run the eval yourself, open a GitHub issue (or a Space discussion) with the model id, backend, and where to find it. We'll run it through the harness and add it.

Submit a score — you ran it

Run the harness on all five test sets, then open a pull request on the GitHub repo committing the two outputs the harness writes:

  1. results/<model-slug>.json — scores and metadata.
  2. outputs/<model-slug>/ — the raw per-dataset transcriptions (<dataset>.jsonl + meta.json), one {"id", "reference", "hypothesis"} per line. Lets reviewers inspect actual transcriptions and enables re-scoring under future normalisers.

Include in the PR description: the exact command you ran, the hardware used (for speed_x context), and whether the model is open or proprietary. On merge, CI automatically publishes both to the HF dataset and updates the leaderboard.

Do not modify the normalisation or metrics — run the harness as-is so results stay comparable.
Verification: whichever path a model arrives by, we re-evaluate it independently on our own hardware before publishing — to confirm the scores reproduce and catch any configuration differences.
Methodology & data changes

2026-08 — Numeral normalisation

  • Spelled-out numerals now fold onto their digit form. Scoring already expanded digits to Danish words so that 38 and otteogtredive count as the same token. That only worked when the model happened to spell a number the way num2words does: a model writing otte og tredive still mismatched, and because Danish compounds are written closed, three tokens against one cost roughly three word errors rather than one. 100 was expanded to ethundrede, which never matched the spoken hundrede. Numerals are now folded to digits first and expanded once, so spelling and spacing variants land on the same form. The scored text is unchanged in kind — still Danish words — only the set of inputs reaching each form is wider.
  • Effect. Near-uniform: most models improve by 0.10–0.14 WER, which shifts every score together and changes no ranking. The exception is MediaCatch/xls-r-300m-danish-mc-v2, which spells numerals out with spaces throughout and improves by 1.06, moving up two places. Measured across all 29 published models before adoption: 28 improve or hold, and the one regression is whisper-tiny at +0.04 WER, already above 130 %.
  • Not adopted: filler-word stripping. Removing Danish hesitation markers (øh, hmm) was measured at the same time and rejected. It changed no ranking across the 29 models, and it is not monotone — whisper-tiny and whisper-base get worse, because at their error rates removing reference tokens raises the rate. It remains available as an opt-in for offline re-scoring.

2026-08 — Decoding fixes & re-runs

  • CTC models decoded with their n-gram LM. Four entries ship a language model in their own repo (the three CoRal Røst wav2vec2 models and MediaCatch). Beam search was being run over the batch padding as well as the speech, so it invented trailing words — badly on MediaCatch, mildly on Røst. Decoding now trims each clip to its true length first. Røst improves by 0.2–1.0 WER, and MediaCatch/xls-r-300m-danish-mc-v2 joins the board.
  • Speed figures corrected, not improved. Those four models now report 3–9× higher speed (x). The models did not change: beam search previously ran single-threaded and now runs in parallel, so the old figures understated them.
  • Short-form vs long-form decoding. The harness passed return_timestamps=True — a long-form setting — to every clip, on a corpus that is ~99 % short-form. On short audio that sends the Danish Whisper fine-tunes into repetition loops (a one-word reference producing 100+ repeated words), badly inflating their WER. Decoding now follows the reference implementations (HF Open ASR Leaderboard, CoRal): plain short-form under 30 s, timestamped long-form above it. Every transformers-backend model was re-run — roest-v3-whisper-1.5b improves from 31.82 to 21.08 WER on CoRal conversation. The wav2vec2 Røst models are unaffected: they use a CTC path that cannot loop.
  • Whisper hallucination on very short clips. Under standard decoding, whisper-large-v3 hallucinates on ~0.6 % of CoRal conversation utterances — a 5-word reference typically yielding ~220 words — emitting memorised training text such as Danish subtitle credits. This seems to be genuine model behaviour rather than a scoring artifact, and is visible in the published raw outputs. Its earlier score was flattered by the non-standard setting above, which happened to suppress the effect for vanilla Whisper while causing the opposite failure in the fine-tunes.

2026-06 — Full re-evaluation & normalisation update

  • Numerals → words. Standalone integers are now spelled out (num2words, Danish) before scoring, so digit-vs-word formatting ("4" vs "fire") no longer counts as an error. Lowers every model's WER by ~0.1–0.5 pp; does not reorder the board.
  • Unicode NFKC. Switched from NFC to NFKC (compatibility folding). A near-no-op on Danish speech text, adopted for correctness and consistency with the Danish standard.
  • Raw outputs published. Every model's un-normalised per-sample transcriptions are now in the results dataset (outputs/), so anyone can re-score under a different normaliser without re-running inference.
  • Long-audio fix (wav2vec2 family). Upgrading to transformers 5.x fixed a silent truncation bug: the previous transformers 4.x processor had no automatic chunking and silently dropped audio beyond ~30 s, inflating WER on the longer test sets. Affected models were re-measured.
  • scribe_v2 (ElevenLabs). Improved markedly vs the prior run — verified to be a genuine server-side model upgrade (the identical audio re-transcribes ~16 pp better on conversational speech), not a scoring change.
  • Speed re-measured on an NVIDIA A100 (80 GB); earlier figures were on an RTX Pro 5000.