History and saved work
History helps you revisit recent calculations. A project gives a saved result a place and a name: Back patio, Garage framing, or Laundry room plumbing is more useful later than a list of anonymous numbers.
When you save a calculation, keep the input measurements and units with its result. A saved number without its assumptions can be hard to interpret a week later.
A practical naming habit
Name the project for the job or location, and title each entry for the thing measured. For example:
| Project | Entry |
|---|---|
| Back patio | Main slab — 12 × 10 ft, 4 in thick |
| Workshop | Floor area — before waste |
| Front steps | Total rise — measured after finish floor |
Notes can explain a measurement that is provisional or a supplier allowance you chose. Keep estimates distinguishable from final measurements.
Everything is local
This version uses an embedded SQLite database. There is no cloud account and no automatic sync between devices. Each installation has its own settings, history, and projects.
Uninstalling the app or clearing its data may remove this database. A browser preview uses browser-local storage and can also lose data when site data is cleared. A preview in a private browsing window should be treated as temporary.
Exporting a backup
Open Settings → Export backup. The preview uses a text-based workflow: review the selectable JSON, choose Copy JSON, and save the complete text as a file in a location you control. Keep the complete document, including its version field.
A backup may contain project names, notes, and measurements. Store it somewhere appropriate for that information. A copy on the same device is useful for some mistakes, but does not protect you if the entire device is lost.
Importing a backup
Open Settings → Restore backup and provide the complete JSON document, or use Paste from clipboard. The app validates the document before applying it in a transaction. It merges records with new identifiers, keeps existing records with the same identifiers, and restores the backed-up settings.
Keep your current backup before restoring another one, particularly if you want to retain your current appearance and unit preferences. Do not edit numeric values or identifiers directly unless you understand the format.
Removing a project
Deleting a project leaves its calculations unfiled rather than deleting those calculations. You can organize them into another project later. Clearing unsaved history also preserves entries you deliberately saved.
A saved result is a snapshot
A saved calculation records the inputs and results from that moment. Changing a default unit preference later should change presentation choices, not the physical meaning of an old measurement.
If the formula or assumptions change in a future release, rerun a calculation deliberately. A history entry should not silently become a different answer.