Esperanto builds numbers up to 999,999 entirely from the invariant particles introduced on the cardinal numbers page. At one million the grammar changes: miliono, miliardo, and higher scale words are nouns, so they take ordinary noun endings and normally introduce the counted item with da.
Build from the largest group downward
Say the thousands first, then hundreds, tens, and units. Within each part, the same small-number rules apply:
| Digits | Esperanto |
|---|---|
| 1,000 | mil |
| 2,000 | du mil |
| 12,000 | dek du mil |
| 42,000 | kvardek du mil |
| 100,000 | cent mil |
| 234,567 | ducent tridek kvar mil kvincent sesdek sep |
Mil is itself an invariant cardinal particle. It stays a separate word from its multiplier: du mil, not dumil. For exactly 1,000, standard usage normally says simply mil, not unu mil.
La urbo havas ĉirkaŭ okdek mil loĝantojn.
The city has about eighty thousand inhabitants.
Ni presis cent dudek kvin mil ekzemplerojn.
We printed one hundred twenty-five thousand copies.
There is no kaj corresponding to the “and” heard in some English varieties. Addition is shown simply by moving to the next place-value group:
La fina prezo estis du mil tricent kvardek eŭroj.
The final price was two thousand three hundred forty euros.
Spelling: what joins and what stays separate
Only multiplied tens and hundreds close up: dudek, tricent, naŭcent. Added parts and all expressions with mil remain separate:
| Operation | Correct | Not standard |
|---|---|---|
| 2 × 10 | dudek | du dek |
| 2 × 100 | ducent | du cent |
| 10 + 2 | dek du | dekdu |
| 2 × 1,000 | du mil | dumil |
| 22,000 | dudek du mil | dudekdumil |
This spelling follows the foundational pattern. Hyphenating an ordinary cardinal such as cent-tridek-du is likewise not the standard way to write 132. Hyphens become useful when a multiword number is turned into a single derived ordinal or noun, such as cent-tridek-dua “132nd,” but that is a different word-building operation.
Ĉu la dosiero vere enhavas naŭcent naŭdek naŭ paĝojn?
Does the file really contain nine hundred ninety-nine pages?
Mil behaves differently from miliono
Up through mil, cardinal particles directly modify a noun and never receive plural or accusative endings:
La firmao dungas tri mil laboristojn.
The company employs three thousand workers.
Laboristojn carries plural -j and object -n. Tri mil remains unchanged.
At 1,000,000, use the noun miliono. Because it is a noun, it has singular/plural and nominative/accusative forms: miliono, milionoj, milionon, milionojn. The following counted material normally comes after da.
Pli ol unu miliono da homoj vizitas la festivalon ĉiujare.
More than one million people visit the festival every year.
La registaro investos du milionojn da eŭroj en la fervojon.
The government will invest two million euros in the railway.
In the second example, milionojn is the direct object and therefore takes -n. Eŭroj follows da and does not take accusative -n.
The same grammar applies to miliardo, biliono, and triliono:
La aparato povas fari miliardojn da kalkuloj en sekundo.
The device can perform billions of calculations per second.
Forms without the noun ending—milion, miliard, bilion—are nonstandard proposals, not ordinary modern Esperanto. Keep the -o and treat these words as nouns.
The long-scale trap for English speakers
Esperanto uses the long scale for the larger -iliono words:
| Esperanto | Value | Modern English equivalent |
|---|---|---|
| miliono | 106 | million |
| miliardo | 109 | billion |
| biliono | 1012 | trillion |
| triliono | 1018 | quintillion |
The dangerous false friend is biliono. It does not mean modern English “billion.” Use miliardo for 1,000,000,000.
La monda loĝantaro superis ok miliardojn, ne ok bilionojn.
The world population exceeded eight billion, not eight trillion.
In scientific and financial communication, digits plus a unit often prevent scale misunderstandings, but when the number is read aloud the Esperanto scale words must retain these values.
Mixed numbers: millions plus smaller groups
A number such as 10,300,978 mixes noun-like milionoj with cardinal particles. The most compact accepted pattern is:
La fonduso administras dek milionojn tricent mil naŭcent sepdek ok da eŭroj.
The fund manages 10,300,978 euros.
The case appears on the noun part milionojn, and da introduces the counted currency after the complete mixed number. Because this mixture combines two grammatical systems, a coordinated version can be clearer:
La fonduso administras dek milionojn da eŭroj kaj tricent mil naŭcent sepdek ok eŭrojn.
The fund manages ten million euros plus three hundred thousand nine hundred seventy-eight euros.
For 1,500,000, several standard forms are possible:
En la regiono loĝas unu miliono kaj kvincent mil da homoj.
One million five hundred thousand people live in the region.
En la regiono loĝas unu kaj duona milionoj da homoj.
One and a half million people live in the region.
The second treats unu kaj duona as the quantity of milionoj. Decimal notation offers another clear option: 1,5 milionoj da homoj, read unu komo kvin milionoj da homoj.
This mixed-number grammar is genuinely less elegant than the simple system below one million. Do not hide that difficulty. In exact data, writing digits and the unit is often clearer; in speech, break the value into audible groups.
Case, quantities, and measured extents
With mil, case remains on the final noun:
La vojaĝo kostis al ni kvar mil eŭrojn.
The trip cost us four thousand euros.
With whole millions, the noun miliono carries the case:
La projekto kostis kvar milionojn da eŭroj.
The project cost four million euros.
This contrast is structural, not optional style. It also prevents an English-speaker error in measured extents. A duration such as du mil horojn places accusative on horojn, never on invariant mil:
La motoro funkciis du mil horojn sen grava riparo.
The engine ran for two thousand hours without a major repair.
Large ordinals, fractions, and clock readings
Derivation applies to a complete number expression. An ordinal adds adjective -a and is commonly hyphenated when the base has several words: mil unu → mil-unua. The resulting adjective agrees like any other adjective:
Ŝi estis la mil-unua vizitanto de la ekspozicio.
She was the one-thousand-and-first visitor to the exhibition.
Fraction words use -on-. Thus milono is one thousandth, while noun-like miliono forms milionono, one millionth:
Unu mikrosekundo estas milionono de sekundo.
One microsecond is one millionth of a second.
Clock hours are ordinal and minutes cardinal; ordinary clock notation stays within the 24-hour system even when a document contains much larger numbers:
La nokta trajno ekiros je la dudek-unua kaj kvardek kvin.
The night train will depart at twenty-one forty-five.
These are productive extensions of the same number structure, not new place-value rules. See ordinal numbers, fractions, and telling clock time for their full inflection and usage.
Years, dates, and large labels
Years are normally written in digits and may be read as ordinary cardinals: 2026 → du mil dudek ses. The full date keeps Esperanto day–month–year order, with an ordinal day and de before the month:
La nova regulo ekvalidos la unuan de Januaro 2027.
The new rule will take effect on January 1, 2027.
Do not copy U.S. English month–day order into the spoken Esperanto sentence. For numeric dates in international documents, ISO 2027-01-01 is unambiguous.
Large numbers can also be labels rather than quantities—paĝo 1208, jaro 2026, ĉambro 1500. A label does not promise that all earlier numbered items exist. See dates and years for the distinction between cardinal year labels and ordinal interpretations.
Writing exact large values
Group digits in threes with narrow spaces: 12 345 678, not a comma that could be confused with Esperanto’s decimal separator. A decimal comma gives 12 345,67. In prose for an international readership, always attach or name the unit.
La raporto registris 12 345 678 vizitojn kaj mezan daŭron de 3,4 minutoj.
The report recorded 12,345,678 visits and an average duration of 3.4 minutes.
— Ĉu la buĝeto estas du milionoj aŭ du miliardoj? — Du milionoj; la tri kromaj nuloj estis eraro.
— Is the budget two million or two billion? — Two million; the three extra zeros were an error.
The exchange shows why grouping and scale words matter: three zeros change miliono into miliardo.
Common Mistakes
Joining mil to its multiplier
❌ La urbo havas kvindekmil loĝantojn.
Incorrect spelling — expressions with mil are separate words.
✅ La urbo havas kvindek mil loĝantojn.
The city has fifty thousand inhabitants.
Treating miliono as an invariant particle
❌ La projekto kostis du milion eŭrojn.
Incorrect — miliono is a noun and requires its ending and normally da.
✅ La projekto kostis du milionojn da eŭroj.
The project cost two million euros.
Translating English “billion” as biliono
❌ La kompanio valoras tri bilionojn da dolaroj.
Wrong if the intended value is three billion dollars; biliono is 10¹².
✅ La kompanio valoras tri miliardojn da dolaroj.
The company is worth three billion dollars.
Putting accusative after da
❌ Ili elspezis kvin milionojn da eŭrojn.
Incorrect — the noun after da does not take accusative -n.
✅ Ili elspezis kvin milionojn da eŭroj.
They spent five million euros.
Copying English date order
❌ La konferenco komenciĝos Marto dek-kvina 2027.
Incorrect — the ordinary Esperanto date puts the ordinal day before de plus the month.
✅ La konferenco komenciĝos la dek-kvinan de Marto 2027.
The conference will begin on March 15, 2027.
Key Takeaways
Keep all expressions with mil separate and invariant, while miliono, miliardo, and higher scale words behave as nouns. Use da after whole noun-like quantities, put case on miliono but on the counted noun after mil, and remember the Esperanto long scale: English “billion” is miliardo. For exact international data, group digits with narrow spaces, use a decimal comma, state the unit, and use unambiguous date order.
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Start learning Esperanto →Related Topics
- Cardinal NumbersA1 — Use Esperanto cardinal numbers to count, quantify noun phrases, identify items, and read basic dates, times, measurements, and decimal notation.
- Ordinal NumbersA1 — Form and use Esperanto ordinal numbers for sequence, labels, dates, clock hours, and ranked noun phrases.
- FractionsA2 — Build exact fractions with the official suffix -on-, then use their noun, adjective, and adverb forms with quantities and units.
- Decimals, Percentages, and Mathematical ReadingB2 — Read and write decimal commas, percentages, signed numbers, and common arithmetic expressions clearly in Esperanto.
- Dates and YearsA2 — Form, inflect, write, and read Esperanto calendar dates and years without importing ambiguous English date order.
- Measures and PriceA2 — Mark bare measures of weight, size, value, and price with -n while distinguishing them from objects and prepositional phrases.