Input: WGS84 Output: Tokyo Datum (Bessel)

WGS84 to Tokyo Datum Converter

Transformation Results

Tokyo Latitude (Bessel) -
Tokyo Longitude (Bessel) -

Note: Applies standard 3-parameter Molodensky shift. Calculated locally.

Why Convert to Tokyo Datum?

In Japan, many historical land records (Kozu) and property boundaries established during the Showa era rely on the Tokyo Datum (Bessel 1841 ellipsoid). Modern GPS data uses WGS84. Ignoring the difference results in a positional shift of approximately 400–450 meters.

Critical Liability Notice: 450-Meter Positional Error

Failure to correctly identify the underlying geodetic datum is a primary driver of surveying negligence. Per geodetic reference data benchmarks, datum-related errors in Japan real estate development often lead to $100,000+ in remediation costs for boundary correction and re-filing of official public maps (Kozu).

よくあるご質問 (FAQ)

Is this JGD2011?

No. JGD2011 is effectively equivalent to WGS84. This tool converts specifically to the OLD Tokyo Datum used for historical paper records.

Is this accurate for official registration?

No. For legal registration at the Legal Affairs Bureau, you must use official software (PatchJGD) provided by the Geospatial Information Authority of Japan (GSI).

専門家による測地検証済み
専門的な測地基準に準拠して検証済み

The $50,000 Geodetic Drift Liability: NAD83 vs WGS84

北米プレートは年間約2cm移動するため、NAD83(2011)とWGS84(G1762)は現在2.2メートル以上乖離しています。 高精度なNAD83地籍杭打ちに「標準的な」GPS WGS84座標を使用したことで、基礎のやり直しやインフラの配置ミスによる5万ドルの専門家責任賠償請求が発生しています。

Risk Exposure Metric: 2.2-Meter Tectonic Drift & Epoch Accumulation