chislo 0.3.1

Convert numbers to Russian words (числа прописью) with grammatical gender, noun declension, ordinals, currency, percentages, durations and dates. Supports i64 integers (quintillions) and decimals with configurable precision.
Documentation

chislo · числа прописью

Turn any number into correct Russian words — gender, declension, currency, dates and all.

Crates.io Documentation CI Downloads MSRV License: MIT

🌐 Live demo & docs · 📖 API reference · 🇷🇺 Русская версия

use chislo::{money, ordinal, date_to_words, Gender, RUB};

money(1234, 56, &RUB);              // одна тысяча двести тридцать четыре рубля пятьдесят шесть копеек
ordinal(2026, Gender::Masculine);  // две тысячи двадцать шестой
date_to_words(2026, 4, 10);        // десятое апреля две тысячи двадцать шестого года

Russian numerals are hard: numbers change form by gender (один / одна / одно), nouns decline by the digit (1 рубль, 2 рубля, 5 рублей), and decimals must agree with an implicit feminine word (одна целая, not один целых). chislo gets all of it right — so your receipts, invoices, payment orders and voice prompts read like a human wrote them.

Why chislo

  • ⚖️ Grammatically correct — three genders, full noun declension, proper decimal agreement.
  • 🧾 Built for documents — money, percentages, durations, dates and times, fractions.
  • 💱 11 currencies out of the box (RUB, USD, EUR, GBP, CNY, JPY, KZT, BYN, UAH, CHF, AED) + ISO 4217 lookup.
  • ⚡ Zero-alloc dictionary — all data is const; Display wrappers format with no extra String.
  • 🪶 Tiny & portable — no_std (with alloc), optional rust_decimal, and WASM bindings.
  • 🦀 i64 range — up to quintillions; scale dictionary reaches 10³⁹.

Install

[dependencies]
chislo = "0.3"
Feature Default What it adds
std ✅ Standard library integration
decimal ✅ rust_decimal::Decimal support
wasm ➖ wasm-bindgen bindings for the browser

no_std: chislo = { version = "0.3", default-features = false }

Quick start

use chislo::{int_to_words, int_to_words_gender, decline, ordinal,
             decimal_to_words, money, Gender, RUB};

// Integers
int_to_words(42);                          // "сорок два"
int_to_words(-1_000_000);                  // "минус один миллион"

// Gender agreement
int_to_words_gender(1, Gender::Feminine);  // "одна"
int_to_words_gender(2, Gender::Feminine);  // "две"

// Noun declension by number
decline(1,  "рубль", "рубля", "рублей");   // "рубль"
decline(5,  "рубль", "рубля", "рублей");   // "рублей"
decline(21, "рубль", "рубля", "рублей");   // "рубль"

// Ordinals, money, decimals
ordinal(42, Gender::Feminine);             // "сорок вторая"
money(100, 0, &RUB);                       // "сто рублей ноль копеек"
decimal_to_words("123.45").unwrap();       // "сто двадцать три целых сорок пять сотых"

Fluent Display API — write numbers straight into format!

use chislo::{Number, Gender, RUB};

format!("{}", Number::new(2026).ordinal(Gender::Masculine)); // "две тысячи двадцать шестой"
format!("{}", Number::new(1234).money(56, &RUB));            // "…рубля пятьдесят шесть копеек"

What's in the box

Area Functions
Integers int_to_words, int_to_words_gender, ordinal
Declension decline(n, one, two, five)
Decimals decimal_to_words, decimal_to_words_precision (1–9 places), decimal_value_to_words
Fractions fraction, mixed_fraction
Money money, money_from_str, money_from_str_rounded, Currency::from_iso
Percent percent, percent_decimal
Duration duration_hms, duration_from_secs
Date & time date_to_words, year_to_words, time_to_words

Full reference and runnable examples: docs.rs/chislo · examples/ (cargo run --example receipt).

Use cases

Fiscal receipts (54-ФЗ) · payment orders & bank statements · invoices, acts, waybills · contracts & powers of attorney · voice assistants / TTS · chatbots that quote amounts.

Links

License

MIT © rekurt

Keywords: number to words russian · russian number converter · числа прописью · склонение · грамматический род · currency to words · Rust crate · chislo