Hello! Lab

Sources & Data Policy

This page explains how Hello! Lab builds and verifies its data. Hello! Project has a long history with many name changes, transfers, and concurrent memberships, so we publish the standards behind our records.

Source Priority

When several sources cover the same fact, we generally use this order of priority:

  1. Hello! Project’s official website and each group’s official website
  2. Agency announcements and official blogs
  3. Wikipedia
  4. Other sources, including news reports and statements by the member

Four Axes for “Same Generation”

Hello! Lab does not reduce the idea of a generation to one rule. It evaluates the following four axes separately.

Group Generation

Did the two members join the same group in the same generation? This is the strongest everyday meaning of “generation-mates” among fans. Morning Musume.’s 9th and 10th generations both debuted in 2011, but the site does not mark them as the same group generation.

Audition Cohort

This axis includes people selected for a group or recruited as Hello Pro Kenshusei through the same audition. Existing trainees promoted alongside the winners are not included. An unrecorded audition history is never treated as proof that two members are from different cohorts.

Trainee Generation

Did the two members join Hello Pro Kenshusei in the same generation? A generation may include more than one intake, so we compare the recorded generation rather than the month of entry.

Hello Pro Egg was renamed Hello Pro Kenshusei in February 2012, so we treat it as the same continuing organization. Hello Pro Kenshusei Hokkaido is treated as a separate organization; matching generation numbers alone do not make members generation-mates.

Debut Year

Did the two members debut in the same year? Members in different groups can match on this axis. When the years differ, the site identifies the senior and junior member.

Groups with More Than One Generation Convention

Some groups were assembled through several additions before receiving their group name, so there is no universally accepted way to count their generations. Hello! Lab treats everyone present when the group received its name as the first generation.

For Tsubaki Factory, the first nine members are Generation 1, the four members known as Litocam are Generation 2, and the three members who joined in 2024 are Generation 3. For BEYOOOOONDS, the original 12 members across CHICA#TETSU, Ame no Mori Kawa Umi, and SeasoningS are Generation 1, while the three members who joined in 2026 are Generation 2. Kobushi Factory, OCHA NORMA, and Rosy Chronicle follow the same named-group rule.

This is an editorial convention, not a claim that research has settled the question. Other sources may count these generations differently.

Groups Without Generation Data

Some group histories—including Country Girls, Berryz Kobo, and ℃-ute—currently have no generation grouping in our records.

This can mean either that the group does not use generations or that we have not yet verified them. Because the database cannot always distinguish those cases, it does not conclude that two members are from different generations. Instead, it says that this axis cannot be evaluated.

We Do Not Fill Gaps with Guesses

When we cannot verify a field, we leave it blank. “Not Yet Verified” means that we do not currently have enough evidence.

For members without a debut, the site distinguishes two situations rather than calling both “unknown debut year”:

  • Current trainee (pre-debut) — a person who may still debut in the future
  • Completed trainee activities without debuting — a person whose trainee period has ended

Member Colors

We compile member-color names from public information and assign display values for the site. These values may differ from official color specifications. A color inferred from its name is marked “approximate” on the member page.

Color is never the only identifier; every circle also includes a name.

Regular Checks

Manual records can contain errors, so we regularly check points such as:

  • whether join and graduation dates are in the correct order;
  • whether any recorded join date precedes a group’s formation;
  • whether generation counts match the displayed records;
  • whether trainee organizations and generation numbers are consistent; and
  • whether official links exist and point to the correct pages.

Errors Can Still Remain

Even with these checks, a source may itself be wrong, or a recent name change or graduation may not yet be reflected. If you notice an issue, please report a correction. We will review the available sources and update the record.