Speech recognition
How to Run Whisper Locally on Your Own Computer
Yes. Whisper runs on your own computer with no API key and no usage fee, after you install an implementation and download a model. Its turbo model needs about 6 GB of video memory, and the right setup depends on whether you have an NVIDIA GPU, a Mac, or only a processor.
Updated October 17, 202612 min read55 cited facts, each traced to its source
6GB of VRAM
The turbo Whisper model needs about 6 GB of video memory, less than the 10 GB the large model needs.
OpenAI, GitHub (openai/whisper), 2026
4times faster, at most
faster-whisper is up to 4 times faster than openai/whisper for the same accuracy, while using less memory.
SYSTRAN, GitHub (SYSTRAN/faster-whisper), 2026
3.9GB of memory
The large model in whisper.cpp needs about 3.9 GB of memory and takes 2.9 GiB on disk.
Georgi Gerganov, GitHub, 2026
Yes. Whisper runs on your own computer with no API key and no usage fee. You install one implementation, download a model once, and transcribe audio from the command line, from Python, or from a desktop app. The official package is released under the MIT License, and its turbo model, the one its command example uses, needs about 6 GB of video memory 1 2 3.
Your hardware decides most of the setup. An NVIDIA graphics card points to faster-whisper. A Mac points to whisper.cpp or MLX. A computer with no suitable GPU can still run whisper.cpp or faster-whisper on the processor. This guide gives the install steps, the memory and speed of each model, and the settings and fixes that matter once Whisper runs. For background on the technology itself, see our guide to Whisper AI.
Whisper runs on your own computer for free once you download a model
Once a model file is on disk, transcription runs on your own processor or graphics card, so the audio does not have to be uploaded to a service. You download the finished model weights rather than training anything yourself.
The first use of a model downloads its file. The openai-whisper package keeps model files in a cache folder, which is ~/.cache/whisper unless you choose another with the --model_dir option 4. Plan for disk space as well as memory. The large model in whisper.cpp takes 2.9 GiB on disk and needs about 3.9 GB of memory 5.
The software itself costs nothing to use. The code and the model weights are released under the MIT License 1. The real costs are your computer's time and memory, which is why the next sections focus on hardware. If you are still choosing a model, our answer on which Whisper model to use explains the trade-off.
Pick an implementation first: openai-whisper, faster-whisper, whisper.cpp, MLX or WhisperX
Pick the implementation by your hardware and by the output you need. All of them run the same family of trained models. They differ in the engine that runs the model, and that engine decides speed, memory use and which computers they suit.
| Implementation | Engine | Best fit | How to install | Watch for |
|---|---|---|---|---|
| openai-whisper | PyTorch, in Python | The reference version, with the default settings | pip install, plus ffmpeg | Slowest in both benchmarks below |
| faster-whisper | CTranslate2, in Python | NVIDIA GPUs, and CPUs in int8 mode | pip install | GPU use needs NVIDIA libraries |
| whisper.cpp | C and C++, no Python needed | Apple silicon, and computers without a GPU | Build from source with CMake, as its README shows | The command-line example reads 16-bit WAV files 6 |
| MLX Whisper | MLX, Apple's framework | Macs with Apple silicon | pip install mlx-whisper | Mac only |
| WhisperX | faster-whisper, plus alignment | Word-level timestamps and speaker labels | pip install whisperx | More setup for speaker labels |
openai-whisper is the reference version, and its README gives the pip command 7. It is the simplest to start with, and it was the slowest in both benchmarks below. Our question on whisper.cpp versus faster-whisper covers that choice.
faster-whisper reimplements Whisper on the CTranslate2 engine. Its README says it is up to 4 times faster than openai/whisper for the same accuracy, while using less memory 8. That is the project's own claim, so check it on your own audio. It does not need a separate ffmpeg install, because it decodes audio with the PyAV library 9. Its GPU mode needs NVIDIA libraries 10, so it suits NVIDIA graphics cards. On a Mac, choose whisper.cpp or MLX instead.
whisper.cpp is a C and C++ port that runs without Python. Its README describes Apple silicon as a first-class target for running Whisper, optimized through ARM NEON, the Accelerate framework and Metal 11. It also runs on CPU-only machines 12. Its command-line example needs 16-bit WAV files, so convert other formats first 6.
MLX Whisper is the port for Apple's MLX framework, which is built for Apple silicon 13. The MLX Whisper README covers its install and command-line use.
WhisperX builds on the faster-whisper backend 14. Its README reports 70 times real-time transcription with the large-v2 model 15. Its main addition is word-level timestamps. The README says Whisper's own timestamps are per utterance, not per word, and can be inaccurate by several seconds 16. Speaker labels, which the README calls speaker diarization, are a separate step with extra setup. See speaker diarization for what that step does.
If you write Python code rather than running commands, our guide to speech recognition in Python compares the libraries.
Model size sets the memory you need and the speed you get
Model size sets two things: how much memory the run needs, and how long it takes. Start with turbo, the model the README's command examples use 2. OpenAI describes it as an optimized version of large-v3 that transcribes faster with minimal degradation in accuracy 17. Use medium or large when you need translation, because turbo is not trained for it 18.
The table lists each model's video memory and its speed relative to the large model. The README warns that real speed depends on language, speaking rate and hardware, so treat the speed column as a ratio, not a promise.
| Model | Required VRAM | Relative speed (large = 1x) |
|---|---|---|
| tiny | About 1 GB 19 | About 10 times 20 |
| base | About 1 GB 21 | About 7 times 22 |
| small | About 2 GB 23 | About 4 times 24 |
| medium | About 5 GB 25 | About 2 times 26 |
| turbo | About 6 GB 3 | About 8 times 27 |
| large | About 10 GB 28 | Baseline |
The .en models are English only. The README says they perform better for tiny and base, and that the difference becomes less significant for small and medium ( OpenAI's model table).
Speed and memory are only half the decision. Accuracy also depends on the language 29. To compare models on your own recordings, measure the word error rate, and see our guide to how accurate speech recognition is for typical figures.
A GPU makes the large models practical, but whisper.cpp runs well on CPUs and Apple Silicon
A GPU is the fastest route for the large models, but you do not need one. In the faster-whisper README's CPU benchmark, whisper.cpp finished the small-model run in 125 seconds, while openai-whisper took 418 seconds on the same 13-minute recording 30 31 32. faster-whisper's int8 mode was quicker still, at 102 seconds 33.
The GPU picture is similar. In the README's GPU benchmark, openai-whisper took 143 seconds with the large-v2 model in fp16 precision 34. faster-whisper in int8 took 59 seconds on the same recording 35.
These benchmarks come from one project's README, on one recording and one set of hardware, so treat them as a guide to the ranking, not a promise for your machine. Our question on whether Whisper can run without a GPU covers the hardware side in more detail.
On a Mac with Apple silicon, whisper.cpp and MLX are the two native routes. The whisper.cpp README lists Metal among its optimizations for Apple silicon 11. Its Core ML option moves the encoder onto the Neural Engine, which the project says can be more than three times faster than CPU-only execution 36.
Quantization is the other lever for memory. Quantized whisper.cpp models require less memory and disk space, and can be processed more efficiently on some hardware 37. The README does not give an accuracy cost for quantized models, so compare the output with the full model on your own audio before you rely on one.
The official Python package needs Python, ffmpeg and one pip command
Installing openai-whisper needs three things: a supported Python, ffmpeg, and one pip command. Then one line transcribes a file. The steps below are for a Mac or Windows computer with a terminal open.
- Install Python. The README says the codebase is expected to be compatible with Python 3.8 to 3.11 and recent PyTorch versions 38.
- Install ffmpeg. openai-whisper requires the ffmpeg command-line tool on your system, in addition to the Python package 39. On a Mac, run
brew install ffmpegwith Homebrew. On Windows, runchoco install ffmpegwith Chocolatey. - Install the package. Run
pip install -U openai-whisper7. If tiktoken has no prebuilt wheel for your platform, the README says you may need Rust 40. - Transcribe a file. Run
whisper audio.mp3 --model turbo. The README uses this command, which selects the turbo model 2.
To get the newest code from the repository, rather than the last PyPI release, the README gives a force-reinstall command 41. Use it when you want a fix that has not reached PyPI yet.
Because openai-whisper hands decoding to ffmpeg, it reads any format that ffmpeg can decode, which is why ffmpeg is a requirement. The whisper.cpp command-line example works differently: it reads 16-bit WAV files, so convert other formats first. The README's example uses ffmpeg to convert an MP3 file into a WAV file first 6.
If you would rather not install anything, our guide to transcribing audio with Whisper, ChatGPT or Gemini covers hosted options, and our question on running Whisper in Google Colab covers a notebook route. Running locally keeps the audio on your computer, which matters for private recordings. Our guide to Whisper and privacy explains what that does and does not protect.
The settings that change results: language, initial prompt, temperature and voice activity detection
Four settings change the transcript more than any other: the language, an initial prompt, the temperature fallback, and voice activity detection. Set the language when you know it. Use a prompt for names and jargon. Leave the temperature and previous-text settings at their defaults unless you see repeated text. Turn on voice activity detection for recordings with long silences.
- Language. In openai-whisper, the language is unset by default and the program detects it 42. Set it with --language when you know the spoken language. The README's example is
whisper japanese.wav --language Japanese. - Initial prompt. The --initial_prompt option supplies text for the first window of audio. Its documented use is to give the model custom vocabulary or proper nouns, which makes those words more likely to be transcribed correctly 43. Keep the prompt short and accurate, because it can also pull the output toward its own words.
- Temperature fallback. When a decode fails its quality checks, Whisper can retry with a sequence of higher temperatures 44. The retries make a run slower, and setting a single temperature turns the fallback off.
- Previous text. --condition_on_previous_text feeds the previous output into the next window. The source says that turning it off can make the text inconsistent across windows, but makes the model less likely to get stuck in a failure loop 45. Change it only if you see repeated or looping text.
- Voice activity detection. faster-whisper includes a voice activity detection filter based on Silero VAD. Passing vad_filter=True turns it on, and its default removes only silences longer than 2 seconds 46. Shorter pauses stay in the audio, so the filter is conservative by design.
Test each change on a short recording with a known transcript before you run a long file. A single setting can help one recording and hurt another.
Desktop apps wrap Whisper for people who do not want a command line
If you do not want a terminal, desktop apps wrap the same engines in a window. Each has its own platforms and install route, so check the project's README before you choose.
- Buzz describes itself as transcribing and translating audio offline on a personal computer 47. Its README lists Whisper.cpp as one of its backends 48. Its Windows app is not code-signed, so Windows shows a warning when you install it 49.
- Vocalinux is a free desktop app for X11 and Wayland, the display systems on Linux 50. After a model is downloaded, it runs speech to text on your machine with whisper.cpp by default 51.
Check each project's README for whether the app transcribes files, dictates into other apps, or does both. If you want to speak into whatever app has focus, our overview of dictation software compares those tools. Yap, which we make, is an on-device dictation app for Mac and Windows, and you can see its options on the download page.
The common errors (ffmpeg missing, GPU not used, out of memory) each have a known fix
Most Whisper problems fall into a few groups. The table pairs each symptom with its usual cause and fix.
| Symptom | Likely cause | Fix |
|---|---|---|
| Python reports that ffmpeg cannot be found | openai-whisper calls the ffmpeg program, which is not installed or not on your PATH 39 | Install ffmpeg, open a new terminal, and check that ffmpeg -version runs in the same terminal you use for Whisper |
| The run is slow and the GPU seems idle | The command line picks CUDA only when PyTorch can detect it, and otherwise uses the CPU 52 | Install a PyTorch build with CUDA support, or use faster-whisper, which needs NVIDIA libraries 10 |
| A warning says FP16 is not supported on CPU | The run is on the CPU, so Whisper switches to FP32 53 | This is a warning, not a failure. Expect CPU speed, or use whisper.cpp or faster-whisper int8 |
| The run runs out of memory | The model is too large for your video memory. The large model needs about 10 GB 28 | Choose turbo, which needs about 6 GB 3, or a smaller model |
| The transcript contains text that is not in the audio | Whisper can produce whole phrases or sentences that are not in the recording. In a 2024 study of Whisper as it stood in 2023, roughly 1 percent of transcriptions contained them 54 55 | Use a voice activity filter, which by default removes only silences over 2 seconds 46, and check the output |
| The text repeats or loops | The model can get stuck in a failure loop, and turning off conditioning on previous text makes that less likely 45 | Try the settings in the section above on a short sample before you change the whole run |
| Subtitles drift out of sync with the speech | Whisper's own timestamps are per utterance and can be off by several seconds 16 | Use WhisperX for word-level alignment |
| Turbo returns English when you asked for a translation | Turbo is not trained for translation 18 | Use medium or large for translation |
Start with one implementation, one model and one short file. Once that works, change one setting at a time and compare the results. For the other options, see our guides to open-source speech recognition and on-device speech recognition, and for the subject as a whole, the speech recognition overview.
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Questions about this
- Can Whisper run without a GPU?Yes. Whisper runs on a processor with no GPU. In the faster-whisper README's benchmark, faster-whisper in int8 mode was the quickest CPU route, and whisper.cpp finished a 13-minute recording in about two minutes with the small model. A GPU is the better choice only when you need the large models quickly.
- How do you install Whisper AI?Install Python 3.8 to 3.11 and ffmpeg, then run pip install -U openai-whisper in a terminal. Then run whisper audio.mp3 --model turbo to transcribe a file. The official route is this Python package, not a downloadable installer.
- How do you run Whisper in Google Colab?Open a new Colab notebook, choose a T4 GPU under Change runtime type, install Whisper with pip, and transcribe your file. Free Colab sessions are not guaranteed and can run for at most 12 hours, so download your transcript before the session ends.
- What are the best Whisper settings for accuracy?Start with the turbo model, or large if your hardware has the memory for it. Set the language yourself, add a short prompt of names and jargon, and keep the default temperature fallback. Leave the no-speech threshold at its default of 0.6 unless a test shows dropped speech or invented text.
- What is the best GPU for Whisper?There is no single best GPU for Whisper. Choose a card with enough video memory for the model you run: about 6 GB for turbo and about 10 GB for large. On a Mac, use whisper.cpp or MLX, which are built for Apple silicon.
- What is the best Whisper GUI or desktop app?No single app is the best for everyone. For a free, open-source desktop app that runs Whisper on your own computer and transcribes files, Buzz is the closest match. For dictating into any app with a keyboard shortcut, Handy and Superwhisper are built for that job, and MacWhisper suits Mac users who transcribe files.
- What is the difference between whisper.cpp, faster-whisper and WhisperX?Pick whisper.cpp for a native build that runs without Python, especially on a Mac or a CPU. Pick faster-whisper for Python work, including transcription on a CPU in int8 mode. Pick WhisperX when you need word-level timestamps or speaker labels, since it adds those to faster-whisper's output.
- Which Whisper model should I use?For most English recordings, use the turbo model. It needs about 6 GB of video memory and scores close to the largest model on English accuracy tests. Pick medium or large for translation, and a smaller model only when your computer cannot run turbo.
- Why is Whisper not using my GPU?Whisper uses your GPU only when PyTorch can detect an NVIDIA card with CUDA. If it cannot, openai-whisper quietly runs on the processor. Run one check in Python: if it prints False, install a CUDA build of PyTorch, then run Whisper again.
More in Speech recognition
- Speech Recognition: What It Is and How Well It WorksThe overview of this topic
- How Speech Recognition Works, From Sound to Text
- What Is Whisper AI? OpenAI's Speech Model Explained
- Speech-to-Text APIs Compared: Price, Accuracy, Speed
- Word Error Rate (WER): How to Calculate and Read It
- How Accurate Is Speech Recognition? The Real Numbers
- Speech Recognition Models: How Neural ASR Works
- Open-Source Speech Recognition: The Best Models
- Speech Recognition Benchmarks and Leaderboards
- Real-Time Speech Recognition: Streaming and Latency
- On-Device vs Cloud Speech Recognition: The Tradeoffs
- Speech Recognition in Python: Libraries Compared
- History of Speech Recognition: From Audrey to Whisper
Referenced by
- Dictation on Windows: Voice Typing, Voice Access, AppsTopic
- Speech Recognition: What It Is and How Well It WorksTopic
- How to Transcribe Audio to TextGuide
- What Is Whisper AI? OpenAI's Speech Model ExplainedGuide
- Speech-to-Text APIs Compared: Price, Accuracy, SpeedGuide
- Is Whisper AI Safe? Privacy and Security ExplainedGuide
- Best Dictation Apps for Mac: Built-In vs Third-PartyGuide
- Open-Source Speech Recognition: The Best ModelsGuide
- Speech to Text on Linux: Dictation on Ubuntu and MintGuide
- Transcribe Audio With Whisper, ChatGPT or GeminiGuide
- Home Assistant Voice: Speech to Text and Voice CommandsGuide
- How to Translate Audio and Video to English TextGuide
- Open-Source Dictation Software: Free Apps on GitHubGuide
- Speech Recognition Benchmarks and LeaderboardsGuide
- Offline Speech to Text on Windows: What WorksGuide
- Real-Time Speech Recognition: Streaming and LatencyGuide
- AI Dictation Cost: Cloud vs On-Device EconomicsGuide
- On-Device vs Cloud Speech Recognition: The TradeoffsGuide
- Speech Recognition in Python: Libraries ComparedGuide
- History of Speech Recognition: From Audrey to WhisperGuide
- Web Speech API: Speech Recognition in the BrowserGuide
- Fluid Dictation, Copilot+ PCs and Windows on ArmGuide
- Can large language models do speech recognition?Question
- Can Whisper run in the browser?Question