Nuvastro vs Co-Star: an honest comparison

Quick verdict: who each one is for

Co-Star is the better pick if you want astrology as a social app. It lives on your phone, sends short daily notifications, and lets you compare charts with friends. Its free tier includes the full natal chart and basic compatibility, which is generous. If most of your astrology happens in group chats with friends, Co-Star was built for exactly that.

Nuvastro is the better pick if you want one quiet daily reading built from your whole chart, plus numerology and a moon calendar in the same place. It is a web app that works on phones, it speaks nine languages, and it sends the daily reading by email. It has no friend network, no compatibility feature and no chat.

If you only want to try something for free and keep it free, Co-Star has the edge. If you want to pay for a focused daily practice that also covers numbers and moon timing, Nuvastro covers more ground per dollar.

One more practical difference: Co-Star expects you to open the app, while Nuvastro can come to you. Its daily reading email means you can read your day in the inbox you already check each morning, which suits people who do not want another app competing for attention on their home screen.

How the readings are made

Co-Star says it uses NASA JPL ephemeris data and generates its daily text with AI. The reading reacts to real-time transits against your chart, which is why two people with the same sun sign get different days. Review sources in 2026 note there is no two-way interaction: you cannot ask a follow-up question about a reading.

Nuvastro also computes planetary positions from an astronomical ephemeris and reads the day against your full natal chart: current transits, the aspects they make to your planets, and the houses they fall in. The output is a written daily reading, available in a simple mode for a quick read and an advanced mode that shows the underlying placements.

Co-Star sells question packs for one-off answers, but there is no back-and-forth chat about a reading. Nuvastro has neither, and no live readers. If an ongoing conversation about a specific event matters to you, you would need a different kind of service.

Tone is the other big difference. Co-Star is known for short, blunt, sometimes cryptic lines that are easy to screenshot. Nuvastro writes plainer, longer explanations that name the transit behind each point, so you can see why the day reads the way it does. Which one feels more useful is personal, and a week with each will tell you quickly.

Natal chart, houses and accuracy

Both apps cast a full Western natal chart. Co-Star does not state publicly which house system it uses; review sources only confirm it is tropical. That matters if you already know your chart from elsewhere and want the houses to line up.

Nuvastro uses Placidus houses when you know your birth time and falls back to whole-sign houses when you do not, so a missing birth time does not leave you with a broken chart. It also lists the major aspects between your planets, and advanced mode shows the degrees.

On raw planetary positions, any product using a modern astronomical ephemeris will agree to a fraction of a degree. The real accuracy question is your birth data. An error of an hour in birth time can move your rising sign and every house cusp, in either app, so check your birth certificate before judging either one.

If you do not know your birth time at all, be wary of any app that still shows confident house placements. Nuvastro switches to whole-sign houses in that case and says so, so you know which parts of the reading depend on the time and which do not. Co-Star's handling of unknown birth times is not stated publicly.

Numerology and the moon calendar

Co-Star does not offer numerology, and a dedicated moon calendar is not confirmed in the sources we reviewed. If you want those, you would need another app alongside it.

Nuvastro includes a numerology profile built from your name and birth date: life path, expression, soul urge, personality and birthday numbers, plus your personal year, month and day. The personal day number sits next to the daily reading so you can see both at once.

The Nuvastro moon calendar shows the moon sign for each day, void-of-course periods, and days that suit particular kinds of tasks. For people who plan around the moon, this is the clearest functional gap between the two products.

Price and trial, as of October 2026

Co-Star is free to download. Its Pro-Star subscription is reported at $8.99-$9.99 per month, and one third-party source reports $59.99 per year. It also sells one-time extras: Eros at $6.99, an advanced chart report at $8.99, Your Year Ahead at $11.99, and question packs from $2.99 to $6.99. A free-trial window is not stated publicly.

Nuvastro has a 7-day free trial with full access and no card required. After that it costs $9.99 per month, $39.99 for six months, or $74.99 per year, with local prices in 11 currencies. There are no one-time add-ons.

On monthly price the two are close. Over a year Co-Star's reported annual price is lower, but its add-ons can push the total up if you buy reports. Nuvastro is simpler to budget because one subscription unlocks everything it has.

Nuvastro also offers a six-month plan at $39.99, which sits between the monthly and annual options and suits people who want to test a longer commitment. Co-Star does not publicly list a comparable middle tier, so your choice there is monthly, annual, or individual purchases as you go.

Where each one clearly wins

Co-Star wins on free access, native apps, push notifications, friend and partner compatibility, and reputation. Its App Store rating is reported at 4.8 from about 206,000 ratings, and it has been an Apple Editors' Choice. Its blunt, meme-friendly tone is a real reason people love it, and Nuvastro does not try to copy it.

Nuvastro wins on breadth for a single subscription: numerology and a moon calendar sit next to the daily reading. It wins on language, with nine supported against Co-Star's English only. It states its house system publicly, and its trial lets you test the paid experience without handing over a card.

Several review sites also report more paywalled features over time. That is a matter of preference rather than a feature, but it is part of why some users look for alternatives.

Switching, using both, and the verdict

You do not have to choose only one. A common setup is to keep Co-Star for friend compatibility and social sharing, and use Nuvastro for the daily reading, numerology and moon timing. Both need the same birth data, so entering it twice takes a couple of minutes.

If you are switching, have your birth date, exact birth time and birthplace ready. If your houses look different in Nuvastro, the likely cause is the house system or a different birth time, not a calculation error.

The verdict: Co-Star is the stronger free, social, phone-native app. Nuvastro is the stronger paid daily practice if you want numerology, a moon calendar, a clearly stated house system and a language other than English. Try the Nuvastro trial for a week before deciding.

If you already pay for Co-Star and mainly use it for compatibility, keep it. If you mainly use it for the daily line and wish it explained more, or you want your astrology in Spanish, Japanese, Turkish or another supported language, Nuvastro is the more natural fit.

Common questions

Is Nuvastro better than Co-Star?

It depends on what you want. Co-Star is better for free use, native apps and friend compatibility. Nuvastro is better if you want numerology, a moon calendar and readings in nine languages.

Does Co-Star have numerology?

No. Co-Star does not offer numerology. Nuvastro includes a full numerology profile with life path, expression, soul urge, personality and birthday numbers plus personal year, month and day.

How much is Co-Star Pro-Star?

As of October 2026, Pro-Star is reported at $8.99-$9.99 per month, with one third-party source reporting $59.99 per year. Nuvastro is $9.99 per month, $39.99 for six months or $74.99 per year.

What house system does Co-Star use?

Co-Star does not state its house system publicly. Nuvastro uses Placidus with a known birth time and whole-sign houses when the birth time is unknown.

Is there a Co-Star alternative without a card for the trial?

Nuvastro offers a 7-day free trial with full access and no card required.