Honestly, when I first entered the trading world, I was also stunned by the number of analytical tools. There’s Wyckoff, Elliott Wave, Ichimoku, MACD, RSI... an unbelievably long list. But there’s one tool that thousands of traders around the world use—across stocks and crypto—and that is đường Fibonacci.

What’s great about đường Fibonacci is that it wasn’t invented by anyone yesterday. In fact, it’s based on a sequence discovered by the mathematician Leonardo Fibonacci more than 700 years ago. I find it quite interesting—a modern trading tool that comes from ancient mathematics like that.

So what is đường Fibonacci? It’s a tool that helps us identify important price levels on the chart through specific percentage ratios. These ratios (23,6%, 38.2%, 61.8%, 78.6%...) are calculated from mathematical relationships in the Fibonacci sequence. You don’t need to do the calculations manually—exchanges already have built-in Fibonacci drawing tools.

Its way of working is also quite logical. You draw the Fibonacci line between two important price points—the highest and the lowest. From that, the Fibonacci levels indicate potential support and resistance zones. In an uptrend, traders look for pullback (retracement) levels to enter positions. In a downtrend, they look for recovery levels to figure out where the price might be blocked.

What’s interesting is that đường Fibonacci also has an expansion (extension) feature, which helps identify potential price targets beyond the current range. Common extension levels are 138.6%, 161.8%, 261.8%, and 423.6%. You can think of them as potential trading targets.

I’ve noticed that the effectiveness of đường Fibonacci isn’t because it has some magical power. Actually, it’s mainly because a lot of traders pay attention to it, so when the price moves toward a certain Fibonacci level, there may be a market reaction. That collective attention is what creates its effectiveness.

But don’t think of đường Fibonacci as a magic bullet. It works best when combined with other indicators—MACD, RSI, or even Elliott Wave. Using it by itself can lead to undesired results. The price might touch a Fibonacci level and react, but it might also just go right through without caring. Risk management is always the most important thing.

One thing I like about đường Fibonacci is that it’s linked to the golden ratio (0,618 or 1.618). This ratio shows up everywhere in nature—from galaxies, to seashells, to the human body. Ancient artists and architects used it to create beautiful works. Even the logos of some famous companies follow this ratio. There’s something magical about it, and I think that’s why many traders trust đường Fibonacci.

In summary, đường Fibonacci is a useful tool if you know how to use it. It helps identify potential areas of interest on the chart, from entry points and price targets to stop-loss levels. But remember, it’s only part of the bigger picture. Combine it with other tools and always manage your risk, and you’ll have a better chance in trading.