Dealing with videos that have either excessively low or high volume is a common headache for content creators. Fortunately, specialized software can assist in adjusting the video volume to the most suitable level.

1. Adjusting Video Volume with Adobe Premiere Pro
Step 1: Open Premiere Pro and click on File (1) => New (2) => Project (3).

Step 2: Name your Project (1) => Click OK (2).

Step 3: Switch to the Audio (1) tab => Double-click Import media to start (2).

Step 4: Select the desired video (1) => Open (2).

Step 5: Drag the video from the Project section and drop it into the Timeline for editing.

Step 6: Once you've placed the video on the Timeline, the editing interface will appear. Simply click and drag the volume slider up or down in the Audio Clip Mixer section.

As shown below, I adjusted the video volume by increasing it by 10dB (1). You'll then notice the yellow icon (Fx) (2), indicating that the sound effect is being applied.
Note: It's advisable to adjust the volume level by around ±10dB for optimal sound quality.

Step 7: Go to the File (1) menu => Export (2) => Media... (3).

Step 8: Next, select Scale To Fit (1) under Source Scaling. If you want to maintain the video's original settings, click on Match Sequence Settings (2). Then, name the file (3) and finally, hit Export (4) to export the video.

After that, the rendering process will take place, so please be patient.

2. Adjusting the volume of your video online with VideoLouder
Step 1: Visit the website https://www.videolouder.com/
Next, click on Browse... to open the video file on your computer.

Then, select the video file (1) => Open (2) to open it.

Step 2: Click on Select action (1) => choose Increase volume to raise the volume or Decrease volume (2) to lower it.

Step 3: Click on the How many decibels (dB)? (1) section and select the appropriate volume increase or decrease level (2) .

Step 4: Once you've finished setting up, press Upload File to complete the process.

Step 5: After completing the video volume editing process, click on Download File to download the file to your computer.

3. Adjusting video volume with TechSmith Camtasia
Step 1: Open Camtasia and click on New Project to create a new project.

Step 2: Click on Import Media... to proceed.

Next, find and click on the video (1) you want to adjust the volume for => Open (2).

Step 3: Left-click and hold the video in the Media Bin and drag and drop it onto Track 2 as shown below.

Step 4: Click once on the video in Track 2 (1) to select it. Then, click on Properties (2) => select the Audio (3) icon => Adjust the volume up or down in the Gain (4) section by sliding the slider left or right.

Step 5: Once you've finished adjusting, save the video by clicking on Share (1) => Local File... (2).

Step 6: Choose Custom production settings (1) => Next (2).

Step 7: Select the video format as MP4 (1) => Next (2).

Step 8: Press Next to continue.

Continue pressing Next to proceed to the next step.

Step 9: Name the File (1), choose where to save the file (2) => Finish (3) to complete.

Afterward, the video rendering process will take place, so please wait a moment.

Step 10: Once completed, a notification like the one below will appear. Click on Finish to complete.

When adjusting the volume in videos, you can customize it quickly and easily to your preference. Remember to adjust the volume moderately, around 10-15dB or 150%, to avoid distortion or unclear sound. Wishing you all success!