# Standard Curve
The **Standard Curve** tab is available for endpoint experiments with standard curve information entered. See [how to enter standard curve info here.](../basic-usage/plate-layout.md#inputting-standard-curve-information)
![Endpoint Graph Results](../../_images/endpoint-graph-results.png)
| Number | Element                        | Description                                                                                                                                                                                                                                                                                                                                                                                               |
| ------ | ------------------------------ | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| 1      | **Group Visibility Toggle**    | Click the checkbox for a group to toggle its visibility in the graph. Wells not assigned to a group can be viewed with the **UNGROUPED** toggle.                                                                                                                                                                                                                                                          |
| 2      | **Select All**                 | Toggle all groups to be visible on the graph.                                                                                                                                                                                                                                                                                                                                                             |
| 3      | **Select None**                | Toggle off visibility of all groups.                                                                                                                                                                                                                                                                                                                                                                      |
| 4      | **View Select**                | Toggle between **Group Average** of the wells assigned to a group or **Individual Wells** to see each well plotted                                                                                                                                                                                                                                                                                        |
| 5      | **Export Graph**               | Export the graph as a `.png` or `.svg` file for lab meetings or presentations. `.png` export size can be selected prior to export. `.svg` images are vector-based so they scale automatically.                                                                                                                                                                                                            |
| 6      | **Standard Curve Graph**       | Measured samples are the samples with known concentrations entered in the [**Endpoint Plate Layout**](../basic-usage/plate-layout.md) and their measured optical density. Those samples are used to calculate a standard curve using the model selected in the **Fit Select**. Unknown or blank groups are added to the graph with the concentration calculated from the equation for the standard curve. |
| 7      | **Fit Select**                 | Choose between **Linear Regression** and **Four-Parameter Logistic Regression (4PL)** as the model to fit the measured samples to an equation. This selection should persist the next time the experiment is opened on the same computer.                                                                                                                                                                 |
| 8      | **Equation Visibility Toggle** | Click to show or hide the equation generated to fit the data. The **R<sup>2</sup>** value denotes how well the curve fits the data with a value close to 1 being a good fit.                                                                                                                                                                                                                              |