Question 1

How do I use the online protractor?

Accepted Answer

Click the '+' button in the Protractor panel to add a protractor to your workspace. Select it by clicking, then use the 'Measure Angle' tool (M key) to add rays. Click to place each ray, and the angle measurement appears automatically. You can add multiple rays to measure several angles at once.

Question 2

Is the online protractor free to use?

Accepted Answer

Yes, this online protractor is completely free with no hidden costs, no registration required, and no usage limits. There are no premium features or paid upgrades. Use it as much as you need for personal, educational, or commercial projects without any restrictions.

Question 3

Do I need to download or install anything?

Accepted Answer

No downloads or installations required. The online protractor runs entirely in your web browser using modern web technologies. Just visit the website and start measuring angles immediately. It works on Chrome, Firefox, Safari, and Edge without any plugins or extensions.

Question 4

Can I upload my own images to measure angles?

Accepted Answer

Yes. Click the camera icon in the toolbar to upload an image from your computer. Once uploaded, you can drag to reposition, resize using corner handles, and adjust transparency in the Image panel. The image stays in the background so measurements remain clear and accurate.

Question 5

How do I get precise angle measurements?

Accepted Answer

Enable angle snapping in the View Options panel to lock rays to whole degrees. Use the grid overlay for precise positioning. You can also enter exact coordinates, rotation, and scale values in the Protractor panel for maximum precision in your angle measurements.

Question 6

What export formats does the online protractor support?

Accepted Answer

Export measurements as JSON (complete workspace data) or CSV (measurement data only for spreadsheets). For images, export as PNG or JPEG at 1x, 2x, or 4x resolution. Choose transparent, white, or black backgrounds. All export options are free with no watermarks.

Question 7

Can I measure multiple angles at the same time?

Accepted Answer

Yes. Add multiple rays to a single protractor to measure several angles simultaneously. You can also add multiple protractors to your workspace, each with its own set of rays. This is useful for complex diagrams or when measuring angles in different parts of an image.

Question 8

Is my work saved automatically?

Accepted Answer

Your workspace is saved locally in your browser's storage. It persists between sessions, so you can close the page and return later to continue your work. For permanent backup, export your workspace as JSON and re-import it when needed. Your data never leaves your device.

Question 9

What's the difference between inner and outer angles?

Accepted Answer

Inner angle is the smaller angle between two rays, ranging from 0° to 180°. Outer angle is the larger angle, ranging from 180° to 360°. Toggle between them in the Protractor panel under Display Options. This is useful when you need to measure reflex angles or complementary angles.

Question 10

How do I delete a ray or protractor?

Accepted Answer

Select the object by clicking it, then press Delete or Backspace on your keyboard. Alternatively, click the trash icon in the right panel. If the delete button is grayed out, the object might be locked - click the lock icon to unlock it first.

Question 11

Which web browsers support the online protractor?

Accepted Answer

The online protractor works on all modern browsers including Chrome, Firefox, Safari, and Edge. We recommend using the latest version of your browser for the best performance. The tool uses HTML5 Canvas and JavaScript, which are supported by all browsers released after 2015.

Question 12

Can I use the online protractor on my phone or tablet?

Accepted Answer

Yes, the online protractor works on mobile devices and tablets. The interface adapts to smaller screens, and you can use touch gestures to interact with protractors and rays. However, for complex measurements, we recommend using a desktop or laptop for better precision and easier control.

Question 13

Does the online protractor work offline?

Accepted Answer

The online protractor requires an internet connection to load initially. Once loaded, basic measurement functions work without internet. However, features like image upload and export require the page to be fully loaded. Your workspace data is stored locally and doesn't require internet to persist.

Question 14

Is my data private and secure?

Accepted Answer

Yes. All measurements and uploaded images are processed entirely in your browser. Nothing is sent to our servers. Your data stays on your device, ensuring complete privacy and security. We don't collect, store, or transmit any of your measurement data or images.

Question 15

Do you collect any personal information?

Accepted Answer

No. The online protractor doesn't require registration, doesn't use cookies for tracking, and doesn't collect personal information. We may use basic analytics to understand page visits, but we don't track individual users or their measurement data. Your privacy is our priority.

Question 16

Can I use the online protractor for commercial projects?

Accepted Answer

Yes. You can use the online protractor for any purpose including commercial projects, client work, and professional applications. There are no licensing fees or usage restrictions. Export your measurements and use them however you need without attribution requirements.

Question 17

Are there any usage limits or restrictions?

Accepted Answer

No usage limits. You can measure as many angles as you need, upload as many images as you want, and export your work unlimited times. There are no daily limits, no file size restrictions (within browser capabilities), and no feature restrictions. Everything is free and unlimited.

Question 18

Is the online protractor suitable for students?

Accepted Answer

Yes, the online protractor is perfect for students learning geometry. It helps visualize angles, understand angle types, and practice measurement skills. Students can upload homework problems, measure angles in diagrams, and export results for assignments. It's free and requires no registration, making it ideal for classroom use.

Question 19

Can teachers use this tool in the classroom?

Accepted Answer

Absolutely. Teachers can use the online protractor for demonstrations, assignments, and interactive lessons. Project it on a screen to show angle measurement techniques, or have students use it on their devices. Export measurements as images for worksheets or presentations. No setup or installation required.

Question 20

How accurate are the angle measurements?

Accepted Answer

The online protractor provides measurements accurate to 0.1 degrees. For most educational and professional purposes, this precision is more than sufficient. Enable angle snapping for whole-degree measurements, or use free positioning for decimal precision. The accuracy depends on your screen resolution and input precision.

Question 21

Why isn't my protractor showing measurements?

Accepted Answer

Make sure you've added at least two rays to the protractor. Select the protractor, click the 'Measure Angle' tool (M key), and place rays by clicking. If rays are present but measurements aren't showing, check that the protractor isn't locked and that you're in the correct measurement mode.

Question 22

The tool isn't loading. What should I do?

Accepted Answer

First, refresh the page and clear your browser cache. Make sure you're using a modern browser (Chrome, Firefox, Safari, or Edge) updated to the latest version. Disable browser extensions that might interfere with JavaScript. If problems persist, try a different browser or contact us with details about your browser and operating system.

Question 23

Can I import measurements from a previous session?

Accepted Answer

Yes. If you exported your workspace as JSON, you can re-import it by clicking the import button in the toolbar. This restores all protractors, rays, measurements, and images exactly as they were. This is useful for continuing work across different devices or sharing measurements with others.

Question 24

How is the online protractor different from a physical protractor?

Accepted Answer

The online protractor offers several advantages: measure angles in digital images, work with multiple protractors simultaneously, export measurements as data, adjust transparency and scale, and undo mistakes easily. Unlike physical protractors, it never wears out, can't be lost, and provides precise decimal measurements. However, physical protractors work without electricity or internet.

Question 25

What makes this online protractor better than other angle measurement tools?

Accepted Answer

This online protractor is completely free with no registration, no ads, and no watermarks. It runs entirely in your browser with no data sent to servers, ensuring privacy. It supports multiple export formats, works on all devices, and offers professional features like multiple protractors, image overlay, and precise measurements. Everything is accessible and easy to use.

Question 26

Can I measure angles in degrees and radians?

Accepted Answer

Currently, the online protractor displays measurements in degrees. Degrees are the most common unit for angle measurement in education and most professional applications. If you need radians, you can convert the degree measurements using the formula: radians = degrees × π / 180.

Question 27

How do I change the color of rays or protractors?

Accepted Answer

Select the ray or protractor you want to modify, then look for the color picker in the right panel. Click it to choose a new color. Different colors help distinguish between multiple measurements, especially when working with complex diagrams or multiple protractors in the same workspace.

Question 28

Can I print my measurements?

Accepted Answer

Yes. Export your workspace as a high-resolution PNG or JPEG image, then print it from your computer. For best results, export at 2x or 4x resolution to ensure measurements are clear when printed. You can also export measurement data as CSV and create a formatted document for printing.

Question 29

What if I make a mistake while measuring?

Accepted Answer

You can undo your last action using Ctrl+Z (Cmd+Z on Mac) or the undo button in the toolbar. To delete a specific ray or protractor, select it and press Delete or click the trash icon. You can also lock objects to prevent accidental changes while working on other parts of your measurement.

Question 30

How do I contact support if I have issues?

Accepted Answer

Visit our contact page to send us an email with your question or issue. Include details about what you were trying to do, what went wrong, and your browser and operating system. We respond to inquiries as quickly as possible. You can also check our tutorials and this FAQ for solutions to common problems.

Frequently Asked Questions

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