Speech-to-text engines

Parakeet (NeMo Speech)

NVIDIA's speech models and toolkit: Apache-2.0 code, and the Parakeet TDT 0.6B v3 model under CC-BY-4.0 with 25 European languages, automatic language detection, punctuation and word timestamps.

Open weightsAlternative to Deepgram, AssemblyAI

What it does

NeMo Speech is NVIDIA's toolkit "for researchers and PyTorch developers working on Speech models", covering speech recognition, text to speech and speech language models. The model most people mean when they say Parakeet is parakeet-tdt-0.6b-v3: "a 600-million-parameter multilingual automatic speech recognition (ASR) model designed for high-throughput speech-to-text transcription", covering 25 European languages and detecting the language automatically.

The model card lists automatic punctuation and capitalisation, word-level and segment-level timestamps, and long audio: up to 24 minutes with full attention on an A100 80 GB, or up to 3 hours with local attention. The README also names newer models: Nemotron ASR Streaming with 40 languages and controllable latency from 80 milliseconds to 1 second, a unified English model that does offline and streaming inference in one network, and Canary for recognition plus translation.

What it replaces

Parakeet replaces Deepgram and AssemblyAI for high-volume transcription of European languages on your own NVIDIA hardware, with the timestamps and punctuation those APIs return.

The label is open weights rather than open source because the weights are CC-BY-4.0, a Creative Commons licence that is not on the OSI list, and the card says training combined a public corpus with an in-house NVIDIA dataset. CC-BY-4.0 does permit commercial use, with attribution. The code around it is Apache-2.0.

Where it falls short: the toolkit expects an NVIDIA GPU. Speaker labelling and quantisation are not described in the README. The desktop dictation apps on this site (Handy, VoiceInk, OpenWhispr, Vibe) already bundle Parakeet for CPU use, which is the easier route for a single machine.

How it runs

pip install 'nemo-toolkit[asr,tts]', a source install with uv, or the NGC Docker container run with all GPUs attached. Python 3.12 or later and PyTorch 2.7 or later. The README states "NVIDIA GPU + CUDA (required for training; recommended for inference)". The model card documents a Transformers path with a CPU fallback and a NeMo-Speech.cpp runtime. NVIDIA links a hosted NIM for the streaming model; no prices are stated.

Who it fits

A team with NVIDIA GPUs transcribing many hours of European-language audio a day. A team on Macs or CPUs should use whisper.cpp, or one of the desktop apps that already ships Parakeet.

Limits the README and card state

Some checkpoints need loading with weights_only off, which the README warns "can have the risk of arbitrary code execution" from untrusted files. The card: "Transcripts may be not 100% accurate", and words absent from the vocabulary "not likely to be recognized".

Sources

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