What is Birthstone Calculator?
A birthstone calculator answers 'what is my birthstone?' by matching a birth month to a recognized modern list of gemstones. Some months have one stone and others have two or three. Instead of combining alternatives into one vague result, this tool gives each birthstone its own image, gem type, typical colors, identifying feature, and general care guidance.
How to use Birthstone Calculator
- Select your birth month from January through December.
- Choose Calculate to see every recognized birthstone for that month.
- Compare the separate stone entries, including typical colors, material, distinctive appearance, and care notes.
- Before buying or cleaning jewelry, verify the stone's identity, treatments, setting, seller disclosures, and return terms.
Features
- Every recognized stone for the selected month shown separately.
- A dedicated icon, gem type, typical colors, and identifying feature for each stone.
- Practical care guidance with a clear reminder that treatments and settings vary.
How the calculation works
The calculator maps the selected birth month to a recognized modern U.S. birthstone list reflected by the Gemological Institute of America, then presents each accepted stone separately instead of joining alternatives with the word 'or.'
Worked example
June returns Pearl, Alexandrite, and Moonstone as three separate birthstones, each with its own image and gem information. March returns Aquamarine and Bloodstone.
Birthstones by month
This month-by-month birthstone chart follows the recognized modern U.S. list used by the calculator. Months with several accepted stones show every option rather than selecting one at random.
| Birth month | Recognized birthstones | Typical color notes |
|---|---|---|
| January | Garnet | Often red; also occurs in other colors |
| February | Amethyst | Purple, from pale lilac to deep violet |
| March | Aquamarine; Bloodstone | Blue to blue-green; dark green with red flecks |
| April | Diamond | Colorless is familiar; natural fancy colors also occur |
| May | Emerald | Green to bluish green |
| June | Pearl; Alexandrite; Moonstone | White or many pearl colors; color-change; soft sheen |
| July | Ruby | Red, from pinkish red to deep red |
| August | Peridot; Spinel; Sardonyx | Green; many colors; layered reddish-brown and white |
| September | Sapphire | Often blue, but many colors occur except gem ruby red |
| October | Opal; Tourmaline | Play-of-color or many body colors; broad color range |
| November | Topaz; Citrine | Topaz occurs in many colors; citrine is yellow to orange |
| December | Tanzanite; Turquoise; Zircon | Commonly associated with blue to blue-violet tones |
Color alone cannot identify a gemstone. Natural variation, treatments, laboratory-grown material, and imitations can look similar without gemological testing.
Why some months have multiple birthstones
Birthstone customs were not created from one universal scientific standard. Lists changed across regions and periods, and later jewelry-industry lists retained or added alternatives that offered different colors, availability, durability, or price points.
Having several recognized stones is therefore not an error. June legitimately includes Pearl, Alexandrite, and Moonstone; August includes Peridot, Spinel, and Sardonyx; and December includes Tanzanite, Turquoise, and Zircon. The calculator presents each option separately so the differences remain clear.
Modern and traditional birthstone lists
A modern birthstone list is a standardized month-based reference commonly used by U.S. gemological and jewelry organizations. Traditional lists can include older alternatives, and regional lists may make different choices.
This calculator uses a recognized modern list for a consistent result, while clearly explaining that other traditions exist. It does not merge every historical or zodiac stone into the month result because doing so would make the answer less precise.
Natural, laboratory-grown, and imitation stones
A natural gemstone forms in nature. A laboratory-grown stone has essentially the same chemical composition and crystal structure as its natural counterpart but is produced in a controlled setting. An imitation only resembles another gem and can be made from glass, plastic, or a different material.
Those categories can differ greatly in rarity, price, disclosure, and identification even when they look similar in a photograph. Ask the seller to state whether the stone is natural, laboratory-grown, treated, cultured in the case of pearls, or an imitation, and request an appropriate report for a high-value purchase.
Choosing and caring for birthstone jewelry
Choose for the way the jewelry will be worn, not only for the month. A frequently worn ring faces more impact and abrasion than a pendant, while pearls and some other materials need gentler handling than harder gems.
Warm water, chemicals, steam, ultrasonic cleaning, sunlight, heat, and sudden temperature changes do not affect every gem in the same way. Follow stone-specific and treatment-specific guidance, store pieces to prevent scratching, and let a professional inspect valuable jewelry when the identity or condition is uncertain.
Common use cases
- Finding every recognized birthstone for a birth month.
- Comparing June, August, December, or another month with multiple stones.
- Choosing a birthday gift by color, material, budget, durability, or style.
- Learning the difference between modern and traditional birthstone lists.
- Preparing questions about treatments, laboratory-grown material, care, and seller disclosure before a jewelry purchase.
Accuracy and limitations
The month mapping follows a recognized modern U.S. birthstone list reflected by the Gemological Institute of America. Birthstone traditions can differ by region and period, and the images and colors are illustrative rather than identification tools. Gemstones may be natural, laboratory-grown, treated, cultured, composite, or imitation. Symbolic meanings are traditions, not health claims, and valuable material should be verified by a qualified gemologist or appropriate laboratory report.
Reviewed 2026-07-16
Sources and further reading
These references support the calculation methods and explanatory content on this page.
- Gemological Institute of America: Birthstones by MonthGemological reference for recognized monthly stones, materials, colors, history, and care.
- Jewelers of America: BirthstonesJewelry-industry overview of birthstone lists and buying context.