Try me: https://shadow.viridian.fish/
This webapp works best with audio routers like Loopback for macOS (or a patient friend). It allows you to record in a reference word, sentence, etc., then record your own voice for comparison.
Developed with Japanese in mind, its primary output is a graph of your pitch over time (for pitch accent comparison). It can also display vowel formants, but the output may be messy depending on the quality of your recording environment.
Create and activate a Python environment:
python -m venv env
source env/bin/activate
Install Python requirements:
cd backend
pip install -r requirements.txt
Install frontend requirements:
cd ../frontend
npm install
NOTE: In addition to the Python and NPM dependencies, you must have Praat and ffmpeg installed on your system to run this app.
To run the server:
cd backend
flask run --port=5000 debug
And to run the frontend (from a separate terminal tab/window):
cd frontend
npm run dev