draftply Download

Skip the script.
Draft the answer.

You have a question. You start typing — numbers, formulas, whatever's in your head. Every line is solved live, right beside it. When the answer holds, wrap it in a form and hand it to anyone. No spreadsheet to wrangle, no Python to debug.

PlatformsiOS · Android · macOS · Windows & Linux
Formatplain text .dply
Networknot required
roof-estimate.dply Editor
draftply editor showing a roof cost estimate — width times length, material cost, VAT and total, all computed live
Why "draft"

A draft isn't the cathedral. It's the working answer — built fast, good enough to act on, easy to hand to the next person.

This started because a decimal point in the wrong place kept breaking the flow. No appetite for a heavyweight spreadsheet, no time to write a script. So: a notepad that does the math, keeps every step in view, and lets you pass the whole thing on. Need the polished, high-performance version later? Port it to Python. For everything in between — draftply.

Module 01 — Draft

A question in your head. Start typing.

No setup, no boilerplate. Open it, type your numbers, label your values, drop in a formula. Like scribbling on a notepad — except every line is solved the instant you write it.

Units4.5 m * 12 m → 54 m²
Percent1200 * 80% → 960
Valuesstay around — reuse them three lines later, or thirty.
budget.dplyEditor
draftply editor with a monthly budget — income minus rent and food, then a 40% savings rate applied to what's left
Module 02 — Solve
analysis.dplyEditor
draftply editor with a Growth class computing compound growth after 10 years, and solve() finding the roots of a quadratic

When arithmetic isn't enough, go deeper.

The language grows with the question. Functions, classes, loops, matrices, statistics, symbolic algebra — all solved live, all in the same document. No imports, no environment, no debugging cycle.

Structurefunctions and classes that read like your thinking
Algebrasolve simplify factor, derivatives, integrals
Datamean std det inv — built in
Module 03 — Form

Give the solution a front panel.

Solved is solved. Add a header block and the document turns into a form: labeled inputs, chip selectors for fixed choices, protected outputs. One switch between editor and front. Nothing is hidden — the math is one toggle away — the form just means nobody has to look at it to get an answer.

Inputtext fields that recalculate as you type
Choicechips for strategy, tax rate, variant
Outputprotected — nothing to break
Sectionsfold a long form into named, collapsible groups
investment-check.dply Form
draftply form view of an Investment Check — amount, years, strategy and tax chips, with future value, gross gain and net gain computed live
Module 04 — Hand off
investment-check.dplybundleOne file. Everything inside.
investment-check.dply
capital-gains.dplylib

Pack it. Send one file.

A .dplybundle packs your document and its libraries into a single file. Whoever opens it sees the form, fills in their own numbers, gets their own answer. If they're curious, the plain text is right there — read it, change it, make it theirs.

Contentsdocument plus libraries, together
Substanceplain text underneath, open to inspect
Transportmail, drive, USB — no server, no account
Module 05 — Quote

Draft it. Hand them the quote.

Line items, a running total, a couple of recognized fields like CustomerName or VatRate — done thinking about it. File → Export offer turns the exact same document into a client-ready PDF — your letterhead on top, a clean item table below, nothing scratch left in. Need the numbers instead of the document? Export offer as CSV writes the same rows — VAT breakdown included — as plain semicolon-separated values for your own spreadsheet.

Itemslabeled lines become rows, total becomes the sum
VATset VatRate and the total row splits into net, VAT and gross — automatically
Letterheadyour company details, or your own header image/PDF
Left outunlabeled math, comments, charts — never printed
tiling-quote.dplyEditor
draftply editor with a tiling quote — customer name, VAT rate, two line items and a running total
tiling-quote.csvExport offer as CSV
ItemAmount
Tiling360.00
Material320.00
Total680.00
plus 19 % VAT129.20
Total amount809.20
Spec sheet

Under the hood

Not a fancy calculator. A real language.

Evaluationevery line in a background isolate, the interface never freezes
Interpreterlexer, parser, evaluator — variables, functions, classes, control flow
Algebrasolve, simplify, factor, derivatives, integrals, polynomial CAS
Matricesdet, inv, transpose, trace, norm; arrays with sort, range, push
Unitskm, m, kg, h, s with automatic SI conversion
Statisticsmean, median, std built in; percentages as 80%
Chartsline, scatter, bar, histogram inline; export SVG, PNG, CSV
Stringsfirst-class text with interpolation: "Total: {x + y} €"
PrintPDF in two columns, code and result side by side
Numberscomma or period, grouping, precision, font — your call
Availability

Editions

Free where it starts. Pro when you need more.

On Apple and Android, start free — one Pro purchase on Apple unlocks iPhone, iPad and Mac together. Windows offers two ways in: a free direct download, or the Store version with a 7-day trial before a one-time purchase. Linux is currently free — no trial, no purchase required.

macOSSoon WindowsSoon LinuxSoon iOSSoon Android

Start with the question.
Hand off the answer.