There is no single best natal chart calculator: the twelve tools here are built for different jobs, and what you can check is what each vendor states about its own tool. For the most house systems, Astro Gold states more than 25 and Astrodienst 23. For a chart without an account, Astrodienst, Cafe Astrology and NatalChart.AI say yes. For chart files that other astrology software opens, look at Astro Gold and TimePassages. If you do not know your birth time, Cafe Astrology lists what it leaves out. For positions you can verify, four tools state the Swiss Ephemeris and Astro-Seek names JPL DE431. NatalChart.AI is our product and one of the twelve, so the table carries no scores.
How to read the table
Each cell is a property the vendor states on its own site, app store listing or help centre, read on . “Not stated” means we found no statement from the vendor; it is not a finding that the feature is missing. The order of the rows is not a ranking, and the row marked as our product follows the same rule as the other eleven: only what is published and can be checked.
Twelve calculators, ten properties
| Tool | Ephemeris stated | House systems | Chart without an account | No exact birth time | Interpretation | Names aspect and orb | Languages | Apps | Export | Price |
|---|---|---|---|---|---|---|---|---|---|---|
| NatalChart.AIour product | Swiss Ephemeris 2.10.03 | Placidus only | yes | computes and marks what is undetermined | AI, from the computed chart | yes, orb in degrees, with applying/separating | 8, interpretation included | iOS · web (no Android) | PDF report and chart poster on MAX · JSON through the API | free · $3.99/wk · $9.99/mo · MAX $19.99/mo |
| Astrodienstastro.com | Swiss Ephemeris (DE441 since May 2026) | 23 | yes, as a guest user | option "unknown" → assumes 12:00 noon | written reports by named astrologers | yes, with applying/separating | 12, not all content translated | web shortcut only | PDF chart drawings | free charts · PLUS $12.90/yr · PDF $39.90/yr · reports from $69.90 |
| Astro-Seek | JPL DE431 (on its ephemeris tables) | 19 | not stated | checkbox "(unknown time)"; effect not stated | reference articles by factor | yes, default orbs published | 9 | not stated | text export for further analysis | free, no paid tier |
| TimePassagesAstroGraph | not stated | 8 named on the web calculator, more on desktop | no, a free account is required | option "Unknown (Use sunrise)" → sunrise chart with solar houses | written by Henry Seltzer; "Not AI" | yes, with applying/separating | 10 (App Store) | iOS · Android · macOS · Windows | .chw · .qck · PDF · JPG · PNG · TIFF | desktop $79 to $699 one-off · Pro $7.99/mo or $59.99/yr |
| Cafe Astrology | not stated | 6 (Placidus default) | yes, no e-mail needed | checkbox "Unknown Time" → omits Moon, ASC, MC, Vertex, Part of Fortune and all house positions | written by the site's own author, Annie | yes, with a worked example | not stated | not stated | print / PDF | free reports · paid reports $2.95 to $16.00 one-off |
| Co-Star | NASA JPL data; no library named | Porphyry, tropical | no, phone or Apple account and SMS code; the web chart needs an e-mail | not stated; "if you can find out what time you were born, we can do the rest" | human astrologers working with AI | aspects listed with exact angles; orb not stated | 1 (English) | iOS · Android | not stated | free with à-la-carte purchases $2.99 to $11.99 · Pro-Star $8.99/mo |
| The Pattern | not stated | Whole Sign | web chart requires an e-mail; app not stated | option "I don't know my birth time"; effect not stated | human-written insights; In-Depth runs on own infrastructure, not third-party AI | square and opposition named by angle; orb not stated | 1 (English) | iOS · Android · web | not stated; data on request by e-mail | free · Go Deeper+ $14.99/mo · $83.99/yr |
| CHANI | not stated | Whole Sign, true nodes, Black Moon Lilith | not stated | no option; help says enter 12:00 noon, "your reading will be less precise" | states it is made by real astrologers, not AI | aspects by whole sign, not by orb; transits by degree | 1 (English) | iOS · Android · web chart tool | not stated | free tier · $11.99/mo · $107.99/yr |
| Astro Gold | Swiss Ephemeris; version not stated | 25+ | not stated for iOS/Android; licence key on macOS/Windows | not stated | built-in interpretations; author not stated | yes, editable orbs, applying/separating separately | 1 (English) | iOS · Android · macOS · Windows | .SFcht, interchangeable with Solar Fire · PDF | iOS lifetime $69.99 · Android $49.99 · macOS $249.99 · Windows $249.99 |
| AstroMatrix | Swiss Ephemeris; version not stated | 8 named | not stated | option "I don't know my birth time" → noon chart with approximate houses | assembled by the vendor's own algorithm from its text library | major aspects and configurations named; orb not stated | 1 (English) | iOS · Android | PDF (premium) | free with ads · subscriptions $2.49/mo to $14.99/yr · lifetime $24.99 to $49.99 |
| Sanctuary | not stated | not stated | not stated | not stated | live 1:1 chat with a human astrologer, tarot reader or psychic | not stated | 1 (English) | iOS · Android · web | not stated | free horoscopes and birth chart details · Sanctuary+ $14.99/mo, $49.99/yr · readings $4.99 to $49.99, per-minute $4.99 to $19.99 |
| AstroSage | not stated | house systems not stated; ayanamsa selectable: Lahiri, Raman, KP, Sayan; North/South Indian chart styles; 16 divisional charts | free kundli stated; account needed to save charts | not stated | AI astrologer chat and live astrologers | "Western aspects" listed; orb not stated | 18 (Google Play) | iOS · Android · web | PDF download, e-mail, Bluetooth | free kundli · paid plans and readings; amounts not stated |
The same cells, one tool at a time with the source pages next to each row, are on the feature matrix. The places where the other tools do more than NatalChart.AI are listed on best AI natal chart tools.
How to choose: five situations
1. You need many house systems
Astro Gold states more than 25 house systems, Astrodienst 23 and Astro-Seek 19. TimePassages names 8 on its web calculator and more on desktop, AstroMatrix names 8, and Cafe Astrology offers 6 with Placidus as the default. Four tools draw one system and say which: Co-Star uses Porphyry, The Pattern and CHANI use Whole Sign, and NatalChart.AI uses Placidus only. AstroSage does not state house systems; it states a selectable ayanamsa (Lahiri, Raman, KP, Sayan) and North and South Indian chart styles. Sanctuary does not state a house system.
2. You want a chart without an account
Astrodienst draws a chart for a guest user, Cafe Astrology asks for no e-mail, and NatalChart.AI calculates the chart without an account. AstroSage states a free kundli, with an account needed to save charts. TimePassages requires a free account. Co-Star needs a phone or Apple account and an SMS code, and its web chart needs an e-mail. The Pattern’s web chart requires an e-mail, and its app does not state it. Astro-Seek, CHANI, AstroMatrix, Sanctuary and the mobile apps of Astro Gold do not state it, so look before you type in birth data; Astro Gold on macOS and Windows runs on a licence key.
3. You need to export
For files that other astrology software opens: Astro Gold writes .SFcht, interchangeable with Solar Fire, and TimePassages writes .chw and .qck. For documents and images: TimePassages also exports PDF, JPG, PNG and TIFF, Astro Gold exports PDF, Astrodienst offers PDF chart drawings, Cafe Astrology states print and PDF, AstroMatrix states PDF on premium, and AstroSage states PDF download, e-mail and Bluetooth. Astro-Seek offers a text export for further analysis. NatalChart.AI exports a PDF report and a chart poster on the MAX plan and JSON through its API; it writes no chart file for desktop software. Co-Star, CHANI and Sanctuary do not state an export, and The Pattern states data on request by e-mail.
4. You do not know your birth time
Astrodienst assumes 12:00 noon when you choose “unknown”, and AstroMatrix draws a noon chart with approximate houses. TimePassages builds a sunrise chart with solar houses. Cafe Astrology omits the Moon, the Ascendant, the Midheaven, the Vertex, the Part of Fortune and all house positions. NatalChart.AI computes the chart and marks what is undetermined. CHANI has no option: its help says to enter 12:00 noon and that the reading will be less precise. Astro-Seek and The Pattern have an unknown-time option without stating its effect. Co-Star, Astro Gold, Sanctuary and AstroSage do not state what happens. What a missing time changes in any chart is on natal chart without a birth time.
5. You want an interpretation and to know what it is based on
The table states two things: who writes the text, and whether the tool names the aspect and the orb behind it. Astrodienst offers written reports by named astrologers, and its aspect tables give the orb with applying or separating. TimePassages is written by Henry Seltzer, states “Not AI”, and names aspect and orb with applying or separating. Cafe Astrology is written by the site’s own author and explains the orb with a worked example. Astro Gold has built-in interpretations, author not stated, with editable orbs. NatalChart.AI writes with AI from the computed chart and gives the orb in degrees, with applying or separating.
Co-Star (human astrologers working with AI), The Pattern (human-written insights), AstroMatrix (the vendor’s own algorithm and text library) and AstroSage (AI astrologer chat and live astrologers) name aspects and do not state an orb. CHANI states it is made by real astrologers, not AI, and reads natal aspects by whole sign and transits by degree. Sanctuary offers live 1:1 chat with a human astrologer, tarot reader or psychic and states nothing about aspects. Astro-Seek has reference articles by factor and publishes its default orbs.
One case sits outside the table: you need a single factor and not a whole chart. The rising sign, the Moon sign and the other single factors each have a page under our calculators, with the birth information each one needs.
Questions
Is there one best natal chart calculator?
Not one that fits everyone. The twelve tools differ in what they are built for: Astro Gold and Astrodienst state the most house systems, Astro-Seek has no paid tier, TimePassages and Astro Gold write chart files for desktop software, and Sanctuary offers live chat with a human astrologer. Choose by the property you need. The table has no scores.
Are free natal chart calculators accurate?
Price does not decide accuracy; the source of the planetary positions does. Astro-Seek is free with no paid tier and names JPL DE431 on its ephemeris tables. Astrodienst draws free charts and states the Swiss Ephemeris. Cafe Astrology's free reports do not state an ephemeris, which means you cannot check it from the page, not that the numbers are wrong.
Why do two calculators put the same planet in different houses?
Usually because they use different house systems, not different astronomy. Co-Star states Porphyry, The Pattern and CHANI state Whole Sign, and NatalChart.AI uses Placidus. The planet's sign and degree stay the same; the house boundaries move. Compare the house system and the time zone before deciding that either chart is wrong.
Can I check a calculator's numbers myself?
Yes. Enter one birth date, time and place and compare the planetary longitudes with NASA's JPL Horizons, a service no astrology vendor controls. NatalChart.AI publishes a fixed test chart with its intermediate values so the comparison can be repeated; the steps are on the Verify your chart page. Differences under an arcminute are usually rounding or display precision. Differences of degrees usually come from the time zone or the zodiac setting.
Do these calculators use the tropical or the sidereal zodiac?
The table records the zodiac only where the vendor states it next to another property. Co-Star states tropical. AstroSage, which states kundli charts in North and South Indian styles, lets you select the ayanamsa: Lahiri, Raman, KP or Sayan. NatalChart.AI is tropical only. For the other tools the zodiac is not part of this comparison, so check the chart settings of the tool you choose.
Which of these calculators have a phone app?
TimePassages and Astro Gold state apps for iOS, Android, macOS and Windows. Co-Star and AstroMatrix state iOS and Android. The Pattern, Sanctuary and AstroSage state iOS, Android and web, and CHANI states iOS, Android and a web chart tool. NatalChart.AI runs on the web and on iOS and has no Android app. Astrodienst states a web shortcut only. Astro-Seek and Cafe Astrology do not state an app.
Sources
Reviewed every four months. Last check 21 September 2026, next 19 January 2027. A vendor can change a price or a feature the day after its page was read, so take each cell as true on the check date and follow the link for today’s value.
The vendor pages below were read on . Each row of the table comes from the vendor’s own site, app store listing or help centre, and from nowhere else.
- NatalChart.AI: natalchart.ai/verify-your-chart · natalchart.ai/llm-hub/natalchart-ai · natalchart.ai/pricing · natalchart.ai/developers, our own pages, kept current with the product.
- Astrodienst (astro.com): astro.com/faq/fq_fh_calc_e.htm · astro.com/faq/fq_fh_owhouse_e.htm · astro.com/faq/fq_de_time_e.htm · astro.com/faq/fq_ma_log_e.htm · astro.com/faq/fq_fh_legend_e.htm · astro.com/faq/fq_hp_lnav_e.htm · astro.com/swisseph/swephinfo_e.htm · astro.com/prod/pr_astroplus_e.htm · astro.com/prod/pr_pdfdraw_e.htm, read 18 September 2026.
- Astro-Seek: astro-seek.com/faq · horoscopes.astro-seek.com/birth-chart-horoscope-online · horoscopes.astro-seek.com/astrology-house-systems-calculator · horoscopes.astro-seek.com/jpl-de431-ephemeris-astrology-online-tables · horoscopes.astro-seek.com/chatgpt-ai-astrology-free-birth-chart, read 18 September 2026.
- TimePassages (AstroGraph): astrograph.com/timepassages/features · astrograph.com/timepassages/mobile · astrograph.com/birth-chart · support.astrograph.com (desktop manual) · apps.apple.com/us/app/timepassages-astrology/id488946918, read 18 September 2026.
- Cafe Astrology: cafeastrology.com/free-natal-chart-report.html · cafeastrology.com/articles/how-to-read-natal-chart-report.html · cafeastrology.com/shop/all-reports/ · astro.cafeastrology.com/natal.php, read 18 September 2026.
- Co-Star: costarastrology.com/faq · costarastrology.com/natal-chart · apps.apple.com/us/app/co-star-personalized-astrology/id1264782561, read 18 September 2026.
- The Pattern: thepattern.com/natalchart · thepattern.zendesk.com (help centre: house system, chart lines, In-Depth, data download) · apps.apple.com/us/app/the-pattern/id1071085727, read 18 September 2026.
- CHANI: chaninicholas.zendesk.com (help centre: chart calculation, aspects, unknown birth time, app pricing, free vs premium) · apps.apple.com/us/app/chani-your-astrology-guide/id1532791252, read 18 September 2026.
- Astro Gold: astrogold.io/get-astro-gold/for-ios · astrogold.io/get-astro-gold/for-android · astrogold.io/get-astro-gold/for-macos · astrogold.io/get-astro-gold/for-windows · astrogold.io/help/faqs, read 18 September 2026.
- AstroMatrix: astromatrix.org/tools/birth-chart · apps.apple.com/us/app/astromatrix-horoscopes/id1065636826, read 18 September 2026.
- Sanctuary: sanctuaryworld.co · sanctuaryworld.co/faq · shop.sanctuaryworld.co/pages/our-app · apps.apple.com/us/app/sanctuary-astrology/id1417411962, read 18 September 2026.
- AstroSage: astrosage.com/kundli · play.google.com/store/apps/details?id=com.ojassoft.astrosage, read 18 September 2026.
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