# 23/resumable.js

A JavaScript library for providing multiple simultaneous, stable, fault-tolerant and resumable/restartable uploads via the HTML5 File API.

Repository: https://github.com/23/resumable.js
Canonical: https://ross.abutalabs.com/products/resumablejs
Language: JavaScript
License: MIT
License Family: permissive
Last push: 2024-02-05T11:30:03+00:00

## Health v2 (maintenance only)
Score: 23/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 0, release rhythm 8, longevity 100
- inputs: {"age_days": 5538, "days_push": 940, "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 4728, forks 605 (observed 2026-08-28T04:08:57.629857+00:00)

## What it is
Resumable.js is a JavaScript library that provides multiple simultaneous, stable, fault-tolerant and resumable file uploads via the HTML5 File API. It splits large files into chunks, retries failed chunks, and lets users pause, resume, and recover uploads after network interruptions.

## Use cases
- upload large files reliably from the browser
- resume uploads after a network connection drops
- pause and resume file uploads without losing progress
- upload files in parallel chunks to speed up transfers
- add drag-and-drop resumable uploading to a web app
- recover interrupted uploads without restarting from scratch

## When to choose
- you need fault-tolerant uploads of large files over HTTP
- users have unstable connections and uploads must resume automatically
- you want a dependency-free browser-side uploader using the HTML5 File API
- you need pause/resume/recover semantics for uploads

## When to avoid
- your target browsers lack HTML5 File API support (very old browsers)
- you only upload small files where chunking adds unnecessary complexity
- you cannot implement the server-side chunk reassembly endpoint
- you need an all-in-one uploader UI widget rather than a library

## Facets
- artifact type: library
- maturity: maintenance
- function: file-upload, http-client
- domain: web-development, frontend, files
- platform: browser
- tags: resumable-uploads, chunked-upload, html5-file-api, large-file-upload, fault-tolerance, javascript

## Member repositories
- 23/resumable.js (main) score 23

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:08:57.629857+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 2026-08-29T18:19:02.634358+00:00, confidence not recorded.
  - readme: https://github.com/23/resumable.js (fetched 2026-08-28T04:08:57.629857+00:00, sha bb474e360b48)
- Data as of 2026-08-30T08:39:29.467469+00:00.