# CAL Command [GstarCAD 2027](Help%20System/GSTARCAD/2027/Index.md) → [Commands](Help%20System/GSTARCAD/2027/Commands/(Commands).md) **Function Description:** This command is used to calculate mathematics and geometry expressions at the Command prompt or within a command. The CAL is an on-line geometry calculator and used to calculate value of point (vector), real numbers, or integer expressions. Those expressions can achieve existing geometry graphic by object snap function (such as: CEN, END and INS). Users can insert an AutoLISP variable to an arithmetic expression and assign the returned value to the AutoLISP variable. It can be used in any commands that need to achieve point, vector, or number. **Command Access:** > **Icon:** / > **Menu:** / > **Ribbon:** / > **Toolbar:** / > **Command:** CAL > **Alias: /** **Command Prompts:** ``` >> Expression: ``` --- **Related References：** - [Commands about the Prompt Calculator (GstarCAD 2026)](../../2026/Commands/00%20Command%20Groups/Commands%20about%20the%20Prompt%20Calculator.md) **Related Tasks：** - [To Start the QuickCalc Calculator (GstarCAD 2026)](../../2026/Commands/01%20Procedures/To%20Start%20the%20QuickCalc%20Calculator.md) --- [Original help](https://www.gstarcad.net/help/GstarCAD_2027_en-US/detail/commandReferences/CAL.html) · © Gstarsoft Co., Ltd.