Angle Converter

無料角度換算ツール — 度、ラジアン、グラードなどを瞬時に換算

OmniConverterの無料オンライン角度換算ツールで、度 (deg)、ラジアン (rad)、グラード (grad)、分角 (arcmin)、秒角 (arcsec) の間を即座に換算。測量で使われる伝統的な「分」「寸」の感覚から現代のラジアン表記までカバー。建築の勾配計算、方位磁石による地図読み、天文学の天体観測まで、プロもアマも使える高精度換算。

使い方

簡単な3ステップで変換できます。

1

角度の値を入力

2

変換元と変換先の角度単位を選択

3

変換後の角度を確認

人気の換算

一般的な基準

参照

1 °°

1 °

参照

1 °rad

0.0174532925 rad

参照

1 °grad

1.1111111111 grad

参照

1 °'

59.99999988 '

参照

1 °"

3599.999712 "

参照

1 °gon

1.1111111111 gon

参照

1 °sign

0.0333333333 sign

参照

1 °mil

17.7777777778 mil

実用的なユースケース

日本では、測量や地図作成に世界測地系(JGD2011 / 日本測地系2011)が使われ、経緯度は度分秒(DMS)または十進度(DD)で表されます。東京駅の位置は北緯35度40分48秒、東経139度46分00秒。建築では、屋根勾配を「寸」や「度」で表します(3寸勾配=約16.7度)。階段の蹴上と踏面の関係から計算される角度は約30度が標準です。数学の授業では、中学校で角度の単位を、高校の三角関数では弧度法(radian)を学びます。カメラの画角は度(°)で表され、広角24mmレンズで約84度、望遠200mmで約12度です。GPSナビゲーションは度/分/秒の形式で位置情報を表示します。航空機の針路は0-360度の方位で示されます。射撃競技ではMOAが命中精度の指標です(1 MOA = 100m先で約2.9cm)。地図投影法(ユニバーサル横メルカトル図法、UTM)では、各ゾーンの中央経線からの角度差が距離に換算されます。太陽光発電のパネル設置角度は、緯度に応じて30-35度が最適とされています。ドローンの姿勢制御ではピッチ・ロール・ヨー角度が使われます。風力発電の風車のブレードピッチ角は度単位で制御されます。AutoCADやVectorworksの標準角度単位は度(°)で、図面に傾斜角度を記入します。

よくある質問

よくある換算の質問への回答

測量での角度単位は?+

日本の測量では度(°)分(')秒(")を使用。1° = 60'、1' = 60"。国土地理院の地図もこの方式です。

勾配(こうばい)の計算は?+

日本の道路勾配は%表示。10% = 約5.71°。鉄道ではパーミル(‰)も使われます。

度をラジアンに換算するには?+

度にπ/180(≈0.01745)を掛けます。

ラジアンを度に換算するには?+

ラジアンに180/π(≈57.296)を掛けます。

直角は何度?+

直角 = 90° = 100 gon = π/2 rad。

グラード(gon)とは?+

400 gon = 360°。測量や土木で使われる角度単位です。

ラジアンは何に使う?+

ラジアンは数学や物理の標準的な角度単位で、三角関数や微積分で使用。

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