# greiman/SdFat

Arduino FAT16/FAT32 exFAT Library

Repository: https://github.com/greiman/SdFat
Canonical: https://ross.abutalabs.com/products/sdfat
Language: C++
License: MIT
License Family: permissive
Last push: 2025-08-13T14:44:36+00:00

## Health v2 (maintenance only)
Score: 40/100 (v2, computed 2026-09-02T17:46:02.011165+00:00)
- activity 36, release rhythm 10, longevity 100
- inputs: {"age_days": 4410, "days_push": 385, "days_rel": 385, "gap_med": 223, "n_releases_24m": 2}
- flags: none
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 1208, forks 550 (observed 2026-08-28T04:03:59.725648+00:00)

## What it is
SdFat is a C++ library for Arduino and other embedded platforms providing access to SD cards with FAT16/FAT32/exFAT filesystems. It supports SPI and SDIO interfaces, UTF-8 filenames, and high-performance read/write operations.

## Use cases
- read and write files on an SD card from Arduino
- access exFAT formatted SD cards on microcontrollers
- log sensor data to SD card
- use SDIO mode on RP2040/RP2350 for fast SD card access
- support UTF-8 filenames on embedded filesystems

## When to choose
- you need FAT16/FAT32/exFAT support on Arduino or RP2040-class hardware
- you need high SD card throughput such as SDIO on Raspberry Pi Pico
- you need Unicode/UTF-8 filenames on embedded devices

## When to avoid
- you are not on an embedded/microcontroller platform
- you need a filesystem other than FAT variants
- your board lacks SPI or SDIO support for SD cards

## Facets
- artifact type: library
- maturity: active
- function: file-system
- domain: embedded-systems, files
- platform: embedded, cpp, iot
- tags: arduino, sd-card, fat32, exfat, microcontroller

## Member repositories
- greiman/SdFat (main) score 40

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:03:59.725648+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 2026-08-30T06:18:55.235131+00:00, confidence not recorded.
  - readme: https://github.com/greiman/SdFat (fetched 2026-08-28T04:03:59.725648+00:00, sha d064dc21de14)
- Data as of 2026-08-30T08:39:29.467469+00:00.