How to negotiate for a better salary.
This.... because for some ridiculous reason, the salary for your next job is based upon the salary of your current or previous job.
That gets right back to how to negotiate for a better salary.
Many HR drones are taught their side of salary negotiation. Tactics like asking you right up front about your previous pay rates and what you expect to be paid for the new job -- all of that done BEFORE you have even discussed what the new job is to be. Before you have talked with them about the duties and responsibilities. Before you have decided if the company is a good fit for you, and before the interviewers have determined if you can be a good fit for them.
Most people are terrible at salary negotiation. Based on various studies with some degree of variance, overall they suggest about 55% of men do not negotiate their wages, and about 70% of women do not negotiate their wages. That is NO NEGOTIATION AT ALL. HR departments have learned that most people will accept whatever low-ball initial offer is made, and companies take advantage of that fact. Of those that do negotiate, most of them do a poor job of it, using the lowball offer as the starting point for negotiating.
Get yourself some salary negotiation books before changing jobs. Ask for more, and use it to negotiate rather than demand.
As someone who has done more negotiation than I'd like with a roughly 3-year layoff cycle in my industry, I've had more practice that I want at this. In one job that I took, there was the initial lowball offer, which I laughed off and said "No, really, we both know that is a low-ball value, try again". Their second offer was a bit better but still below prevailing wages. So then, using negotiation tactics, I reiterated all the things I had done, all the benefits they were likely to see from me, and suggested a much higher value, about 3.5x their initial lowball. After a few more back-and-forths, and we settled on a good wage. Later in leadership when I was in a position to see everyone's salary, I could see how many of the people in the company -- notably most of the non-confrontational people and mediocre performers -- had wages similar to the initial lowball offers. Most of those who were assertive or high producers tended to have much higher wages. I don't understand how they are related, but they are clearly correlated.
Learn to negotiate. It is an important life skill. It applies directly to salary negotiation, but also to many other facets like getting the good projects and pushing back on corporate demands, including for software development learning to negotiate features from a bad list of requirements to a good set of easily producible items.