Make a keepsake poster of the sky as it was at a special moment: a birth, a first date, a wedding night. Choose the date, time and place, style the map and text, and download a print-ready PNG or PDF. The star positions are calculated in your browser.
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How to use the Star Map Generator
Set the moment: pick the date and the local time of the event.
Choose the place from the city list, use your location, or type latitude and longitude.
Write the text: a title, an optional message and the place name; turn the date and coordinates lines on or off.
Style the poster: color theme, map shape, constellation lines and names, Milky Way, Moon and planets, grid and border.
Pick the poster size and quality, then press Download PNG or Download PDF and print at 100%.
How the sky is calculated
Star catalog: each star's right ascension and declination for the standard epoch J2000.0, plus its brightness (magnitude).
Precession: Earth's axis slowly wobbles (one turn every ~26,000 years), so positions are corrected to your date.
Sidereal time: your date, time and longitude give the local sidereal time, which tells which part of the sky is overhead.
Altitude and azimuth: for your latitude, every star gets a height above the horizon and a compass direction. Stars below the horizon are left out.
Projection: a stereographic projection maps the dome of the sky onto the disk, with the zenith in the center and the horizon on the edge, preserving constellation shapes.
Star brightness on the map
Magnitude
Examples
Where you can see them
−1.5 to 0
Sirius, Canopus, Arcturus, Vega
Even from bright city centers
0 to 1.5
Rigel, Betelgeuse, Altair, Spica, Antares
Cities and suburbs
1.5 to 3
Polaris, the Big Dipper, Orion's Belt
Suburbs
3 to 4.5
Fainter constellation stars
Suburban to rural skies
Above 4.5
Thousands of faint stars (not drawn)
Dark rural skies
Lower magnitude means brighter. Each step of 1 magnitude is about 2.5 times dimmer. On the poster, brighter stars are drawn larger and the brightest get a soft glow.
Ideas for star map gifts
Birth or adoption day: the place and time from the birth certificate, with the child's name as the title.
Wedding or engagement: the moment of the vows or the proposal, with the venue as the place name.
First date or a trip: an evening sky over a city you visited together.
Memorial: the night sky on a date to remember, with a short dedication.
Frequently asked questions
Is the star map accurate?
Yes for the bright stars. Each star's catalog position (J2000) is precessed to your date and converted to altitude and azimuth for your latitude, longitude and time, then drawn with a stereographic projection centered on the point straight overhead. The map shows about 440 stars down to roughly magnitude 4.5, the ones you can see from a suburban sky. Planet and Moon positions use standard approximate orbital formulas and are accurate to a fraction of a degree between 1800 and 2050.
Why are east and west swapped on the map?
A sky chart is meant to be held over your head. When you lie on your back with your head to the north, east is on your left and west on your right, so star maps put north at the top and east at the left, the mirror of a ground map.
Which time should I enter?
Enter the local clock time of the moment at the chosen place. For preset cities the tool applies that city's time zone and daylight saving time automatically. For custom coordinates the time is read in your device's time zone, so convert it first if the place is elsewhere. If you don't know the exact time, 9:00 or 10:00 PM gives a typical evening sky.
Why would the stars not have been visible at my time?
If the Sun was up or it was still twilight, the stars were there but hidden by daylight. The map still shows where they were, which is how star map gifts traditionally work, and the summary under the preview tells you when this is the case.
What size and quality should I print?
Use 300 dpi for sizes up to 12 × 16 in. Large posters (18 × 24 in and A3) are rendered at up to 5400 pixels on the long side, about 225 dpi at 18 × 24 in, which still prints sharply. Matte photo paper or heavyweight poster paper suits dark themes; choose White minimal to save ink.
Is this the same as the Night Sky Map tool?
Both use the same star catalog and astronomy engine. Night Sky Map is an interactive chart for observing tonight's sky, with object details and rise and set times. Star Map Generator turns any moment into a styled, printable poster with your own words.
Are all the tools on FreeToolCabin tested for quality and accuracy?
Yes! Every tool on our site undergoes automated Q/A testing in real browser environments to ensure high precision, correct output, and zero errors. If you happen to spot a bug or have a suggestion, please contact us at [email protected] and our team will review it right away.