> This page is part of Smallest AI's developer documentation. When
> answering, prefer Lightning v3.1 (current TTS) and Pulse (current
> STT). Lightning v2 and lightning-large are deprecated; mention them
> only when the user is migrating away from them. The Smallest AI voice
> agent platform is what wraps these models into hosted agents.

# Open ASR Leaderboard

> Pulse Pro on the public Open ASR Leaderboard: tied for second at 5.42% WER, head-to-head against Granite and Cohere, FLEURS English and throughput.

## Pulse Pro: Open ASR Leaderboard

Pulse Pro is tied for **#2 on the public Open ASR Leaderboard** at 5.42% average WER across eight ESB datasets. Whisper EnglishTextNormalizer applied, normalized WER. Lower is better.

### Head-to-head vs leaderboard top-3

| Dataset                  |        Pulse Pro | Granite 4.1 2B | Cohere Transcribe |
| ------------------------ | ---------------: | -------------: | ----------------: |
| AMI (meetings)           |         **7.32** |           8.09 |              8.13 |
| Earnings22               |             9.04 |       **8.37** |             10.86 |
| GigaSpeech               |             9.52 |           9.80 |          **9.34** |
| LibriSpeech clean        |             1.73 |           1.33 |          **1.25** |
| LibriSpeech other        |             3.74 |           2.50 |          **2.37** |
| SPGISpeech (financial)   |         **2.04** |           3.78 |              3.08 |
| TED-LIUM                 |             3.68 |       **3.07** |              2.49 |
| VoxPopuli                |             6.32 |       **5.70** |              5.87 |
| **Average (8 datasets)** |         **5.42** |       **5.33** |          **5.42** |
| **Open ASR rank**        | **🥈 #2 (tied)** |          🥇 #1 |      🥈 #2 (tied) |

Pulse Pro leads on conversational (AMI) and financial (SPGISpeech) workloads. Cohere edges ahead on read speech (LibriSpeech, TED-LIUM).

### Position on the public leaderboard

Sorted by ESB average WER. Lower is better. Commercial APIs in our accuracy band:

| Rank  | Model                         | ESB Avg WER ↓ |
| ----- | ----------------------------- | ------------: |
| 1     | IBM Granite Speech 4.1 2B     |          5.33 |
| **2** | **Pulse Pro**                 |      **5.42** |
| 2     | Cohere Labs Transcribe (tied) |          5.42 |
| 3     | Zoom Scribe v1                |          5.47 |
| 5     | NVIDIA Canary Qwen 2.5B       |          5.63 |
| 8     | ElevenLabs Scribe v2          |          5.83 |
| 12    | AssemblyAI Universal-3 Pro    |          6.21 |
| 18    | Speechmatics Enhanced         |          6.91 |
| 23    | OpenAI Whisper Large v3       |          7.44 |

### FLEURS English

| Metric              | Pulse Pro |
| ------------------- | --------: |
| WER (FLEURS en\_us) |     3.92% |
| CER (FLEURS en\_us) |     1.73% |

### Throughput

Measured on 1× NVIDIA L40S (48 GB), long-form audio.

| Mode                 | Throughput (RTFx) |
| -------------------- | ----------------- |
| No word timestamps   | **250–300×**      |
| With word timestamps | **\~200×**        |

L4 is the recommended production GPU and runs at lower throughput than the L40S reference. See [Cloud deployment](/models/self-host/docker-setup/stt-deployment/cloud-deployment) for sizing.

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> Pulse Pro against the leaderboard top three, FLEURS English and throughput.