Glossary

Auction houses typically charge a buyer's premium of 15-25% on top of the winning bid (hammer price). When analyzing sale data, it's important to know if prices include or exclude this premium. PlateIndex normalizes prices where possible.

Bookend plates have the same digit at the beginning and end, creating visual symmetry. Examples include 101, 12341, and 58975. The pattern is represented as A...A in letter-form notation.

Example: 101, 12341, 58975

Comparable plates are selected using pattern matching, digit count, price range, and sale recency. They provide market context by showing what similar plates have sold for. Minimum 5 comparables are needed for reliable analysis.

Confidence levels indicate data reliability: High (20+ sales, 80%+ auction data), Medium (10+ sales, 50%+ auction data), Low (fewer than 10 sales or limited auction data). Higher confidence means more reliable pricing analysis.

Custom plates are personalized plates that can be ordered new from VicRoads. Unlike heritage plates, custom plates can contain letters and have various style options. They typically have lower collector value than heritage plates due to their availability.

PlateIndex aggregates data from multiple sources: auction houses (most reliable), licensed brokers, and verified private sales. Auction data is prioritized due to public nature and verified transactions. Source mix affects confidence level.

Example: Shannons Auctions, Pickles, Private Sale

Double plates contain two of the same digit in a row. While more common than triples, doubles still add collector appeal, especially when combined with other patterns. Letter-form: AA or AABB.

Example: 11, 44, 7788, 1122

Free tier provides 5 searches per day with access to basic plate information, historical prices, and pattern identification. Advanced features require Pro subscription.

The freshness indicator shows how recently the data was refreshed. Fresh data (<24 hours) is shown in green, recent data (24-72 hours) is default, and stale data (>72 hours) shows a warning. Data is typically updated daily.

Heritage plates are Victorian license plates that have been in continuous registration since their original issue. These plates are valued for their historical significance, low numbers, and unique patterns. Unlike custom plates, heritage plates cannot be newly created and their scarcity drives their collector value.

Example: 1, 888, 12321

Letter-form notation uses letters to represent the structural pattern of plate numbers, abstracting away the specific digits. For example, 121 becomes ABA, and 1234 becomes ABCD. This notation helps identify pattern families regardless of specific numbers used.

Example: 121 → ABA, 1234 → ABCD, 111 → AAA

Low number plates are those with only one or two digits. These are the rarest heritage plates as they were among the first ever issued in Victoria. Single-digit plates can sell for hundreds of thousands of dollars, with plate "1" being the most valuable.

Example: 1, 7, 13, 42, 99

Lucky 8 plates contain one or more 8s, which are considered extremely auspicious in Chinese culture. The number 8 sounds similar to the word for "prosperity" in Chinese. Triple 8s (888) and quad 8s (8888) command significant premiums, especially from buyers with Chinese heritage.

Example: 8, 88, 888, 8888

Market trend shows how prices have changed over selected periods (3-month, 6-month, 12-month). Calculated as: ((Current Median - Previous Median) / Previous Median) × 100. Positive trends indicate appreciation, negative trends indicate declining values.

Median price is the middle value in a sorted list of all sale prices. Unlike average (mean), median is resistant to extreme outliers. If there are sales at $10k, $15k, and $200k, the median is $15k while the average would be $75k. Median better represents the "typical" sale price.

Mirror plates use rotationally symmetric digits (0, 1, 8) to create numbers that appear identical when turned upside down. Examples include 1001, 8008, and 1881. This unique visual property adds collector interest.

Example: 1001, 8008, 1881, 10801

Palindrome plates contain numbers that read identically in both directions, such as 121, 12321, or 456654. They are highly valued by collectors for their mathematical symmetry and visual appeal. In letter-form notation, palindromes are represented as ABA, ABCBA, or ABBA.

Example: 121, 12321, 456654, 1001

Patterns are the structural characteristics of plate numbers that make them collectible. PlateIndex recognizes 8 pattern types: palindrome, sequential, lucky 8s, low number, triple, double, bookend, and mirror. A single plate can have multiple overlapping patterns.

Pro subscribers get unlimited searches, advanced analytics, PDF exports, pattern alerts, and priority support. Free tier users are limited to 5 searches per day with basic features.

The Rarity Score is a proprietary metric that measures how rare and desirable a plate number is. It considers pattern types (35%), digit count (25%), number value (20%), and market activity (20%). Higher scores indicate rarer, more valuable plates.

Sample size (shown as n=X) indicates how many verified sales are included in calculations. Larger samples provide more reliable statistics. We recommend treating data with n<10 as indicative only.

Sequential plates contain numbers in consecutive order, either ascending (123, 4567) or descending (321, 7654). These patterns are popular for their mathematical order and are represented in letter-form as ABC, ABCD, or CBA.

Example: 123, 4567, 321, 9876

Triple plates contain three or more of the same digit in a row, such as 111, 777, or 9999. The repetition creates visual impact and memorability. In letter-form, these are represented as AAA or AAAA.

Example: 111, 333, 777, 9999

Wildcard search allows you to find plates matching a pattern using * to represent any digit(s). For example, *88* finds all plates containing 88, and 1*1 finds palindromes starting and ending with 1.

Example: *88*, 1*1, 123*, *999