Install & Compatibility
Where this runs
tested against v? · pip install
Install × environment matrix
Each cell = how many times install + import succeeded across repeated harness runs. Partial = flaky.
glibc = Debian/Ubuntu slim · musl = Alpine Linux
muslpy 3.10–3.910 runs
build_error
glibcpy 3.10–3.910 runs
build_error
Code
Verified usage
Verified import paths — ran on the pinned version, not inferred.
nemo.collections.asr
✓ import nemo.collections.asr as nemo_asr
nemo.collections.tts
✓ import nemo.collections.tts as nemo_tts
nemo.collections.nlp
✓ This module was removed in NeMo 2.6.1. Refer to NeMo documentation for alternatives.
✗ import nemo.collections.nlp as nemo_nlp
The entire `nemo.collections.nlp` module was removed in NeMo v2.6.1. Code relying on it will break. Check the latest documentation for updated NLP functionalities.
This quickstart demonstrates how to load a pre-trained ASR model and transcribe an audio file. The model will be downloaded automatically on the first run. Ensure you have a `.wav` audio file (preferably 16kHz mono) at the specified `filepath`.
import nemo.collections.asr as nemo_asr
# This will download and load the pretrained model from NVIDIA's NGC cloud
# The first run takes time to download the model (~1.5 GB)
asr_model = nemo_asr.models.EncDecRNNTModel.from_pretrained(model_name="stt_en_fastconformer_hybrid_large_ctc_rnnt")
# Path to an audio file (replace with your own or download an example)
# For demonstration, we'll use a placeholder. In a real scenario, you'd have an actual .wav file.
# Example audio can be found in NeMo's tutorials or downloaded from public datasets.
# For example: !wget https://nemo-public.s3.us-east-2.amazonaws.com/example_samples/audio_0.wav
filepath = "./audio_0.wav" # Ensure this file exists for the code to run
# For demonstration, let's create a dummy file if it doesn't exist
import os
if not os.path.exists(filepath):
try:
import torchaudio
import torch
sample_rate = 16000
duration_seconds = 5
waveform = torch.sin(2 * torch.pi * 440 * torch.arange(0, sample_rate * duration_seconds) / sample_rate).unsqueeze(0)
torchaudio.save(filepath, waveform, sample_rate)
print(f"Created dummy audio file: {filepath}")
except ImportError:
print(f"Warning: '{filepath}' not found and torchaudio not installed to create a dummy file. Quickstart may fail.")
transcriptions = asr_model.transcribe([filepath])
print(f"Transcription: {transcriptions[0]}")
nemotoolkit --version
Debug
Known issues
breakingThe entire `nemo.collections.nlp` module was removed in NeMo v2.6.1. Any code that imports or uses classes/functions from this module will break.fixReview the NeMo documentation for updated NLP capabilities or alternative approaches for versions 2.6.1 and later. Some functionalities may have been migrated or require different import paths.
affects: < 2.6.1 to > 2.6.1
gotchaNeMo requires a specific PyTorch version to be installed *before* installing NeMo itself, compatible with your CUDA version (if using GPU). Installing NeMo without pre-installing PyTorch can lead to dependency conflicts or incorrect CUDA setups.fixAlways install PyTorch with the correct CUDA version first, then install `nemo_toolkit[all]`. Refer to the official NeMo installation guide for specific PyTorch/CUDA version compatibility.
affects: All versions
gotchaSome functionalities, especially for ASR, had compatibility issues with NumPy 2.0 prior to NeMo v2.6.1.fixUpgrade to NeMo v2.6.1 or newer to ensure full compatibility with NumPy 2.0. If unable to upgrade, you might need to pin NumPy to an older version (e.g., `numpy<2.0`).
affects: < 2.6.1
gotchaUsers of `numba-cuda` and `cuda-python` packages (often implicit dependencies for GPU acceleration) experienced installation and usage issues in earlier versions.fixEnsure you are on NeMo v2.7.2 or newer, as specific fixes for these packages were introduced in recent releases. If issues persist, verify your CUDA toolkit installation and driver versions.
affects: < 2.7.2
gotchaNeMo models (especially large language models or pre-trained ASR/TTS models) require significant GPU memory and disk space for downloading model checkpoints. Running on CPU is possible but much slower.fixEnsure you have adequate GPU VRAM (e.g., 8GB+ for many models) and sufficient disk space. For production, consider deploying on NVIDIA GPUs. For local development, be mindful of model sizes.
affects: All versions
Upgrade
Version history
3.0.0latest on PyPI · released Aug 7, 2026
Audit
Dependencies
torchrequiredCore deep learning framework. NeMo requires a specific, user-installed PyTorch version compatible with their CUDA setup. Installing PyTorch *before* NeMo is crucial.
pytorch-lightningrequiredUsed for model training and research. NeMo builds on Lightning's capabilities.