IndexedDB — where your "saved" file actually sits

Reference page for Loft IndexedDB usage. Updated when stores or fields change. Last reviewed 2026-05-27.

Definition

IndexedDB is a database the browser maintains on your device, per origin. Web pages call it to create databases, store structured records (including binary Blobs), query and update them. The data stays on the user’s machine, is scoped to the site’s origin, and survives tab close.

It’s the natural persistence layer for a local-first tool: the operator can’t query it after the fact, and the user can wipe it at will.

Properties (vs alternatives)

Property	IndexedDB	localStorage	server-side DB
Max storage	gigabytes (browser-quota’d)	~5 MB	unbounded (operator cost)
Structured objects	yes	strings only	yes
Binary Blobs	yes	no (base64 only)	yes
Synchronous	no (async API)	yes (blocking)	network round-trip
Per-origin scoped	yes	yes	yes
Survives “Clear site data”	no	no	yes (operator)
Operator can query	no	no	yes
Costs operator money	$0	$0	yes

Loft’s IndexedDB stores

loft-pins

The pinned-tool list. One row per tool you’ve pinned, with:

• toolId — unique tool identifier
• toolPath — URL path to the tool
• pinnedAt — timestamp
• version — build version at pin time
• buildSha — build SHA for cache-validity checks
• refreshedAt — last successful refresh timestamp
• (no file content)

loft-folders

User-created folder groupings for pinned tools. One row per folder, keyed by a generated id.

loft-compare-pdf-cache (per-tool)

The Compare PDF tool’s parsed-PDF cache. Stores parsed metadata keyed by file fingerprint so a second compare of the same file is fast. The original PDFs are not stored — only parsed metadata.

Per-tool small preferences (various)

A handful of tools persist single-row preferences in IndexedDB (or localStorage for smaller items): last-used compression level, preferred crop ratio, default colour. Scoped to the tool that wrote it.

Loft’s Cache Storage namespaces

These are Service Worker caches, not IndexedDB. They live under Cache Storage in the Application panel and are managed by the service worker rather than by page-side JavaScript.

loft-shell

The offline shell — /offline.html and the install-time stash. Populated on SW install.

loft-assets

Runtime-fetched code chunks (/_astro/ bundles). The SW keeps this bounded and evicts older entries during cleanup.

loft-pinned

HTML and assets for every tool you’ve pinned offline. The SW never removes entries from this cache during its own cleanup routine, though the browser can still evict it under storage pressure like any other origin data.

loft-ocr

Opt-in OCR model weights fetched on first OCR use. None of the content you OCR’d is stored here — only the model files.

loft-pv (Workbox background-sync queue)

A short-lived queue used to replay deferred page-view beacons when the network is unavailable. Entries expire after 24 hours. No file content, no user identifiers.

What is never stored

A negative list because the positive list keeps getting longer in subtle ways. None of the following ever land in Loft’s IndexedDB:

• The file you ran a tool on.
• The text OCR extracted from your file.
• Any identifier we maintain for “you” (we have no accounts).
• Cross-site tracking IDs.
• Analytics user IDs.
• Cookies for non-essential purposes.

How to inspect it yourself

DevTools → Application tab → IndexedDB in the left sidebar. Expand the databases under your Loft origin. Each database lists its stores; each store lists its rows. You can read every row, edit it, or delete it from the panel.

For a clean slate: DevTools → Application → Clear storage → Clear site data. Wipes everything.

Properties of the data once stored

Once data is in Loft’s IndexedDB:

• Origin-scoped. Only pages served from lofttools.com can read or write it. Cross-origin access is blocked by the browser.
• Not encrypted at rest by default. Browsers store IndexedDB as files on disk in a browser-specific format. Modern OSes encrypt the volume; that covers IndexedDB transitively. If you require app-level encryption, that’s a feature we’d need to ship deliberately per tool (the File Encryption tool does this for its outputs).
• Per-browser. Switch from Chrome to Firefox and you start fresh in Firefox. Same origin, different browser = different IndexedDB.
• Subject to quota eviction. Browsers cap total origin storage at a few hundred MB to a few GB. When heavy, older entries get evicted. The loft-pinned cache is not touched by the SW’s own cleanup, but is still subject to quota-based eviction by the browser like any other origin data.

Update policy

This page is updated when Loft adds, removes, or changes the schema of an IndexedDB store. If you spot a mismatch between what’s documented here and what Application → IndexedDB shows on the live site, send us a note. The store list above is current as of 2026-05-27.