Export Withings weight and blood pressure to CSV or SQL

The Withings app (Health Mate) can send you a one-off export of your measurements as CSV files. When you want more than a one-off file, Open Health Sync pulls your Withings data through the Withings API and keeps it in a PostgreSQL database you run: every weigh-in, body composition reading and blood pressure measurement, in the same columns as your other devices. You can export it again at any time as CSV or Parquet, read it over an API, or query it in SQL.

1. Start an instanceCopy Anchor Link

Follow the quickstart to Start the stack: clone the repository, create .env with a fresh encryption key, and start it with Docker Compose. Then create your own user:

docker compose --env-file .env -f deploy/docker-compose.yml exec -T ohs \
  /ohs admin personal setup > ~/.ohs.env
chmod 600 ~/.ohs.env
set -a; . ~/.ohs.env; set +a

No Withings keys yet? ohs seed --demo writes 90 days of synthetic data that includes a Withings scale and blood pressure monitor (weight, body fat, lean mass, systolic and diastolic pressure, heart rate), so you can try every step below first (demo data).

2. Connect your Withings accountCopy Anchor Link

Withings data reaches the API through a Withings developer application that you register yourself:

1. In the Withings developer dashboard (developer.withings.com), create an application with the callback URL <OHS_PUBLIC_URL>/oauth/withings/callback (details).

2. Add its keys to .env and restart:

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   OHS_WITHINGS_CLIENT_ID=...
   OHS_WITHINGS_CLIENT_SECRET=...

3. Open Withings' consent page and allow access:

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   python3 recipes/connect.py withings

The first data arrives a few seconds later. The connector backfills the last 30 days, then pulls every 6 hours and whenever Withings notifies a new measurement. Check that the backfill is done when pending_jobs reaches 0:

curl -s "$OHS_URL/v1/users/$OHS_USER/coverage" -H "Authorization: Bearer $OHS_KEY" | jq .pending_jobs

3. Export to CSV or ParquetCopy Anchor Link

One measurement at a time, with type:

curl -sOJ "$OHS_URL/v1/users/$OHS_USER/exports/samples?type=body_mass&format=csv" \
  -H "Authorization: Bearer $OHS_KEY"
curl -sOJ "$OHS_URL/v1/users/$OHS_USER/exports/samples?type=blood_pressure_systolic&format=csv" \
  -H "Authorization: Bearer $OHS_KEY"

Or everything at once, one file per list:

python3 recipes/export-all.py                     # CSV, into health-export-<date>/
python3 recipes/export-all.py --format parquet    # Parquet, for pandas, Polars or DuckDB

Sleep, workouts and ECG recordings have their own exports (sleep, workouts, ecg), and the full list is in the Withings connector guide.

Every row has a provider column, withings here. Add start and end (YYYY-MM-DD) for a window. Columns and types are described in CSV and Parquet exports.

import pandas as pd
weight = pd.read_parquet("health-export-2026-10-19/samples.parquet")
weight = weight[(weight["provider"] == "withings") & (weight["type"] == "body_mass")]
print(weight.set_index("start_date")["value"].resample("W").mean().tail(12))

4. Query it with SQLCopy Anchor Link

Open psql in the database container, with your user id in a variable:

docker compose --env-file .env -f deploy/docker-compose.yml exec postgres \
  psql -U ohs -d ohs -v user="$OHS_USER"

Weight, week by week:

SELECT date_trunc('week', start_date)::date AS week,
       round(avg(value)::numeric, 1) AS kg
FROM ohs_data.quantity_samples
WHERE user_id = :'user' AND provider = 'withings' AND quantity_type = 'body_mass'
GROUP BY week
ORDER BY week DESC
LIMIT 12;

Blood pressure readings, systolic and diastolic side by side. Withings sends both values of one reading with the same time, so they pair on start_date:

SELECT s.start_date, s.value::int AS systolic, d.value::int AS diastolic
FROM ohs_data.quantity_samples s
JOIN ohs_data.quantity_samples d
  ON d.user_id = s.user_id AND d.start_date = s.start_date
 AND d.provider = 'withings' AND d.quantity_type = 'blood_pressure_diastolic'
WHERE s.user_id = :'user' AND s.provider = 'withings'
  AND s.quantity_type = 'blood_pressure_systolic'
ORDER BY s.start_date DESC
LIMIT 20;

Point Grafana, Metabase or a notebook at the same database for charts (build a dashboard).

What the Withings API does not giveCopy Anchor Link

The backfill covers the last 30 days. Older measurements are not pulled, so for years of history, start from the Health Mate CSV export or, on an iPhone that syncs Withings to Apple Health, import the Apple Health export. From then on the connector keeps everything new.

NextCopy Anchor Link

• Keep it running: new readings arrive on Withings notifications and scheduled pulls, and the same export picks them up next time.
• Add your other devices: every connector exports in the same columns.
• Get the data as FHIR R4 to hand it to a doctor's or a research system.