🪐 Planet Name Generator: Random Sci-Fi World Names
By Shihab Mia · Updated 2026-07-11
Choose your options and press Generate.
This planet name generator invents random sci-fi world names in a single click, so you never have to stare at a blank page again. Choose how many names you want (1 to 20) and an optional style, and the tool mixes coined names built from syllable banks (like Xeloria or Vandros), classical and mythic roots, and realistic catalogue designations in the Kepler-442b or Alpha Lyrae IV style. Every batch is unique, nothing repeats, and you can copy any name with one tap or grab the whole list at once.
What is the Planet Name Generator?
Good planet names tend to fall into a few recognisable families, and this generator draws from all of them so your worlds feel varied instead of samey. The first family is the coined name: an invented word assembled from an opening cluster, a soft middle vowel sound, and a rolling ending, giving results such as Xeloria, Vandros, or Zephyrune. These read as alien yet pronounceable, which is exactly what you want for a planet a character has to say out loud. Because the parts are combined at random from large banks, the number of possible coined names runs into the tens of thousands.
The second family leans on classical and mythic roots. Real astronomers have named worlds and moons after Greek and Roman figures for centuries, so pairing a mythic-sounding prefix with a flowing suffix (Nyxaris, Thalassor, Erebusoria) instantly signals gravitas and history. This style suits older, storied civilisations or planets that a setting treats as legendary. It sits halfway between pure invention and real naming convention, which makes it a safe default when you want something evocative but not too outlandish.
The third family is the catalogue designation, and it is the most scientifically grounded. Modern exoplanets are named after the telescope or survey that found them plus a number and a lower-case letter for the planet, which is why you see names like Kepler-442b, TRAPPIST-1e, or Gliese-581g. The letter matters: the star itself is "a", so the first planet discovered is always "b", the second "c", and so on. A close cousin is the Bayer-style stellar designation, a Greek letter plus the Latin genitive of a constellation, optionally with a Roman numeral for the orbit, giving names such as Alpha Lyrae IV or Tau Ceti III. These feel like entries in a star catalogue because that is precisely how real stars are labelled.
Randomness quality matters more than it first appears. This tool uses the browser cryptographic random number generator (crypto.getRandomValues) rather than the ordinary pseudo-random function, and it rejects values that would introduce modulo bias, so every syllable and every survey code is equally likely. Within a single batch it also tracks the names it has already produced and skips any duplicate, so a list of twenty names is twenty genuinely different worlds. Nothing is sent to a server: the entire generator runs in your browser, which means it works offline and never logs the names you create.
When to use it
- Naming planets, moons, and colonies for a science-fiction novel, short story, or screenplay.
- Building star systems and worlds for a tabletop campaign in Traveller, Stars Without Number, or a homebrew setting.
- Populating a galaxy map or 4X-style game world with dozens of distinct planet names quickly.
- Generating placeholder world names for game development, worldbuilding wikis, or prototype levels.
- Sparking ideas when you are stuck, then tweaking a generated name into something you love.
- Creating usernames, server names, or project code names with an outer-space theme.
How to use the Planet Name Generator
- Set how many planet names you want, from 1 up to 20.
- Pick a naming style, or leave it on Mixed to blend coined, mythic, and catalogue names.
- Press Generate. A fresh batch of unique names appears instantly, with a first batch shown on load.
- Click Copy next to any name to copy it on its own, or use Copy all to grab the whole list.
- Not quite right? Press Generate again for a completely new set of worlds.
Formula & method
Worked examples
Build a coined planet name from the syllable banks.
- Pick an onset at random from the opening bank: "Xel".
- Pick one vowel core: "a" (a coin flip decides whether to add a second core; here it does not).
- Pick an ending from the coda bank: "ria".
- Join the parts: Xel + a + ria to "Xelaria", then normalise the capitalisation.
Result: A coined world name such as Xelaria or, with a second core, Xeloria.
Build a catalogue designation in the Kepler-442b style.
- Pick a survey code from the catalogue list: "Kepler".
- Pick a catalogue number, here a value between 100 and 9999: 442.
- Pick the planet letter, remembering the star itself is "a", so planets start at "b": choose "b".
- Join them with a hyphen before the number: Kepler-442b.
Result: A catalogue-style designation such as Kepler-442b or Gliese-581e.
The naming styles this generator uses
| Style | How it is built | Example results |
|---|---|---|
| Coined | Invented word from onset + vowel core + ending | Xeloria, Vandros, Zephyrune |
| Classical / mythic | Mythic prefix + classical suffix | Nyxaris, Thalassor, Erebusoria |
| Catalogue | Survey code + number + planet letter | Kepler-442b, Gliese-581e |
| Greek-letter (Bayer) | Greek letter + constellation + Roman numeral | Alpha Lyrae IV, Tau Ceti III |
How real exoplanet designations are read
| Part | Meaning | Example |
|---|---|---|
| Survey or catalogue name | The telescope or catalogue that recorded the star | Kepler, TRAPPIST, Gliese |
| Number | The star index within that catalogue | 442, 1, 581 |
| Lower-case letter | The planet, starting at "b" (the star is "a") | b, c, d in order of discovery |
Common mistakes to avoid
- Starting a catalogue planet at the letter "a". In real exoplanet naming the star itself is "a", so the first planet discovered around it is always "b". A world called Kepler-442a would be the star, not a planet. This generator always starts planets at "b".
- Making every name unpronounceable. A wall of consonants like "Xkthzvorn" is hard to read and harder to remember. Coined names work best when an opening cluster is followed by a vowel sound, which is why this tool always inserts a vowel core between the parts.
- Reusing the same name within one setting. Two planets with the same name confuse readers and players. The generator guarantees no repeats inside a single batch, but if you generate several batches, check across them before committing a name.
- Mixing incompatible naming conventions. A gritty hard-science story full of Kepler-style catalogue names can feel jarring if one planet is suddenly called Nyxaris. Pick a style that matches your tone, or use Mixed deliberately when the variety fits your galaxy.
Glossary
- Exoplanet
- A planet that orbits a star other than the Sun. Thousands have been confirmed, most named after the survey that found them.
- Catalogue designation
- A name built from a survey or catalogue code, a number, and a letter, such as Kepler-442b, used for real discovered worlds.
- Bayer designation
- A star name made of a Greek letter plus the Latin genitive of its constellation, such as Alpha Lyrae, dating from 1603.
- Coined name
- An entirely invented word assembled from syllable parts, designed to sound alien yet pronounceable.
- Genitive
- The possessive Latin form of a constellation name used in star designations, so Lyra becomes Lyrae and Cetus becomes Ceti.
- Modulo bias
- A subtle skew that appears when random numbers are shrunk to a range with a simple remainder. This tool rejects biased values so every option is equally likely.
Frequently asked questions
Are the generated planet names free to use?
Yes. The names this tool invents are randomly assembled words and designations with no copyright attached, so you are free to use them in novels, games, campaigns, or any project. As with any generated name, it is worth a quick search to make sure a favourite is not already strongly tied to an existing franchise.
How many different planet names can it create?
A very large number. The coined style alone combines dozens of onsets, vowel cores, and endings, which multiplies into tens of thousands of possibilities, and the catalogue style adds thousands more from its numbers and letters. In practice you will almost never see the same name twice.
What is the difference between the naming styles?
Coined names are invented words like Xeloria that sound alien but readable. Mythic names pair classical roots for a storied feel, such as Thalassor. Catalogue names copy how real exoplanets are labelled, like Kepler-442b. The Greek-letter style follows the Bayer convention for stars, such as Alpha Lyrae IV. Mixed blends all four.
Why does the catalogue style use the letter "b" and not "a"?
Because that is how astronomers actually name exoplanets. The star at the centre of a system is treated as "a", so the first planet found around it is designated "b", the second "c", and so on. Starting at "b" makes the generated names look authentic rather than made up.
Will I get the same names as everyone else?
No. Each name is chosen with the browser cryptographic random generator, which produces a different sequence every time for every visitor. Two people generating twenty names at the same moment will almost certainly get twenty completely different worlds.
Can I use these names for stars, moons, or spaceships too?
Absolutely. Nothing about the output is locked to planets. The coined and mythic names work well for moons, colonies, or starships, and the Greek-letter style is literally a star-naming convention, so it suits suns and systems especially well.