# Exporting and saving

Source: https://meptools.com/tools/duct-pressure-drop-calculator/docs/exporting-and-saving/

The calculator offers four ways to get a result out: the clipboard, a share link, a PDF
calculation record, and a saved project.

## Copy results

**Copy results** puts a plain-text summary on your clipboard — shape, flow (as entered and in
m³/s), length, velocity, Reynolds number and regime, friction factor, Σ K, the straight and
fitting drops, the total, and the disclaimer. It is meant for pasting into an email or a
transmittal note, not for archiving: it records the answer, not enough of the inputs to
rebuild it.

## Share link

The rail's **Share** button (and the File menu's **Copy share link** row) copies a URL of the
current tool page with your inputs packed into a single `#i=` fragment — one opaque, base64-
encoded blob, not separate named parameters. Opening it loads the calculator with those inputs
already filled in — useful for sending a colleague the exact case you are looking at without
saving anything to an account. Nothing is calculated until the recipient presses **Calculate**
themselves. The button confirms with **Link copied** once the URL is really on your clipboard,
or **Copy failed** if the browser refused the write.

The blob carries every scalar input (airflow value and unit, duct length, shape, width/height or
diameter, roughness preset and value, air temperature and pressure, Σ K mode, manual Σ K), the
duct role by key (`main`, `branch` or `none`), and the fitting schedule as one entry per row
(fitting key, quantity, override). There is no per-field query-string mapping to read off the
URL — the fragment is opaque by design.

Three things to know:

- **Inputs are read once, at page load.** Editing the address bar on a page that is already
  open does nothing — open the link in a new tab, or reload.
- A **project name is not part of the link**, and neither is any account context. A share link
  is inputs only.
- Fitting rows whose key is not in the current library are **dropped** rather than guessed at,
  so a link made against a future library version degrades to the rows still recognised. Check
  the schedule after opening a link someone sent you.

## PDF calculation record

**Print** and **Export PDF** are offered on three surfaces, each with its own label: the action
rail (**Print** / **Export PDF**), the File menu's Report group (**Print report** / **Export
PDF**), and the **Report** evidence block itself (**Print / Save as PDF** / **Export branded
PDF**). All three are disabled until Calculate has produced a current result — there is no way
to print or export an incomplete or stale calculation, so what you export always matches what
is on screen.

Export PDF renders a _Duct Pressure Drop — Calculation Record_ containing:

- a KPI grid: total pressure drop (Pa and mmH₂O), velocity, friction rate, Reynolds number
  and regime, Σ K;
- every input, including the roughness preset, air state, Σ K mode and the fitting library
  version;
- the formula, with each symbol's value substituted;
- the pressure-drop breakdown (straight / fittings / total);
- the fitting schedule table, listing each row's quantity, effective K, contribution, and
  whether the K came from the library or from your override;
- any warnings; and the disclaimer.

The PDF is **rendered on the server from your raw inputs** — the calculation is redone there
rather than trusting the numbers your browser displays, so the report can never disagree with
the tool.

PDF export requires a plan that grants the `export.pdf` entitlement. Without it the button
carries a **PRO** badge and routes you to the upgrade page rather than exporting; the
restriction is enforced on the server as well as in the interface. See
[Plans and payments](/docs/plans-payments).

## Saving projects

Saving requires an account — signed out, the File menu offers **Sign in to save & manage
projects** instead of the save actions. See [Projects](/docs/projects) for how saved projects
are organised across tools.

| File menu        | Effect                                                                       |
| ---------------- | ---------------------------------------------------------------------------- |
| **New**          | Detaches the current project and clears the inputs to defaults.              |
| **Load project** | Opens a saved MEC-01 project.                                                |
| **Save**         | Saves to the current project. Keyboard: `Ctrl` + `S` (`Cmd` + `S` on macOS). |
| **Autosave**     | Toggles automatic saving; the menu shows **On** or **Off**.                  |
| **Save As**      | Saves as a new project.                                                      |
| **Rename**       | Renames the current project.                                                 |

A saved project stores your **inputs only** — the calculation is redone from them on load,
so opening an old project always reflects the current library and equations rather than a
frozen answer. The breadcrumb shows the tool code, version and project name, and the save
indicator reports saved / unsaved / saving.

This tool has **no undo history** and no in-tool reset action. **File → New** is the only way
to clear every input back to its default, it detaches the current project immediately, and the
only recovery is your last save.