# subsurface/subsurface

This is the official upstream of the Subsurface divelog program

Repository: https://github.com/subsurface/subsurface
Canonical: https://ross.abutalabs.com/products/subsurface
Homepage: https://subsurface-divelog.org
Language: C++
License: GPL-2.0
License Family: copyleft
Last push: 2026-08-26T04:32:06+00:00

## Health v2 (maintenance only)
Score: 67/100 (v2, computed 2026-09-02T17:46:02.011165+00:00)
- activity 99, release rhythm 8, longevity 100
- inputs: {"age_days": 5478, "days_push": 7, "days_rel": null, "gap_med": null, "n_releases_24m": 0}
- flags: none
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 3171, forks 598 (observed 2026-08-28T04:07:47.470032+00:00)

## What it is
Subsurface is a free, open-source dive log application for recreational, technical, and free divers that runs on Windows, macOS, Linux, Android, and iOS. It downloads dives from dive computers, imports logs from other programs, plans dives with Bühlmann ZH-L16 or VPM-B models, and computes dive statistics.

## Use cases
- download dives from my dive computer
- log and organize scuba dives across devices
- plan a technical dive with Bühlmann or VPM-B
- import dive logs from other divelog software
- track dive statistics like SAC rate and gas pressures
- view my dive log on my phone
- store my dive logbook in the cloud

## When to choose
- you need a free cross-platform divelog not tied to a specific dive computer brand
- you are a tech diver needing deco planning with VPM-B or Bühlmann ZH-L16
- you want cloud sync and mobile access to your logbook

## When to avoid
- you need a commercial product with vendor support
- you only want a simple paper-log replacement without dive computer integration

## Facets
- artifact type: application
- maturity: active
- function: gui, data-visualization, file-system
- domain: cross-platform, desktop-applications, mobile-development, developer-tools
- platform: windows, cross-platform
- tags: divelog, scuba-diving, dive-computer, dive-planner, qt, cloud-sync, decompression-planning, macos, linux, android, ios, desktop, mobile

## Member repositories
- subsurface/subsurface (main) score 67

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:07:47.470032+00:00.
- Health v2: computed from the inputs above; adoption is never an input.
- Inferred fields (summary, facets, guidance): AI-extracted, prompt v1, taxonomy v1, on 2026-08-29T18:45:29.024768+00:00, confidence not recorded.
  - readme: https://github.com/subsurface/subsurface (fetched 2026-08-28T04:07:47.470032+00:00, sha 4761061e5b91)
  - homepage: https://subsurface-divelog.org (fetched 2026-08-29T09:39:36.887214+00:00, sha d21fb19d4aa5)
  - site_page: https://subsurface-divelog.org/documentation (fetched 2026-08-29T09:39:36.896520+00:00, sha 5c5d1d1d0d72)
  - site_page: https://subsurface-divelog.org/faq (fetched 2026-08-29T09:39:36.898383+00:00, sha 174e3bfec335)
- Data as of 2026-08-30T08:39:29.467469+00:00.