The closing prices of a rebar futures contract for 5 consecutive trading days are 3800, 3820, 3810, 3830, and 3850 (RMB/ton). Open the "Moving Average" module in the calculator above, enter these 5 numbers, select a period of 5, and the current value of the 5-day moving average will immediately display on the right as 3822 RMB/ton. This is the example we will walk through step-by-step below.

Principles and Formulas

The Simple Moving Average (SMA) is one of the most commonly used technical indicators. The formula is:
SMA = (P₁ + P₂ + … + Pₙ) / n
Where P₁ to Pₙ are the closing prices (or specified prices) of the most recent n periods, and n is the number of periods.

The intuition behind this formula is to filter out daily noise and reveal the trend direction by averaging prices over a past period. For example, if the 5-day moving average is higher than the current price, it indicates that recent prices are below the average cost, suggesting short-term weakness.

Complete Example: Calculating the 5-Day Moving Average

Using rebar futures as an example with the calculator above:

Enter 3800, 3820, 3810, 3830, 3850 in the "Closing Price Sequence (comma-separated)" input box;
Enter 5 in the "Period" input box;
Click the "Calculate MA" button;
The right side of the calculator will display "5-Day Moving Average = 3822.00" (rounded to two decimal places).

Interpretation: Is 3822 higher than the last closing price of 3850? No, 3822 < 3850, which means the current price (3850) is above the moving average, indicating a relatively strong short-term trend. However, note that a short period makes the signal highly sensitive.

More Examples: Comparing Different Periods and Price Sequences

Comparative Example 1 (10-Day Moving Average): Using the same sequence but changing the period to 10, the calculator will prompt "At least 10 data points are required." This edge case demonstrates that the number of periods cannot exceed the number of data points.

Comparative Example 2 (Moving Average During a Price Decline): Suppose the sequence is changed to 3900, 3880, 3850, 3820, 3800 (continuous decline). Entering a period of 5 gives a moving average = (3900+3880+3850+3820+3800)/5 = 3850. Interpretation: 3850 > the last closing price of 3800. The moving average is above the price, forming resistance and confirming a downtrend.

Interpreting the Results

Relationship Between MA and Current Price	Signal Meaning
MA < Price	Short-term price is above average cost; bullish trend bias
MA > Price	Short-term price is below average cost; bearish trend bias
MA ≈ Price (within ±0.5%)	Consolidation; direction unclear

Important: Moving averages are lagging indicators and cannot predict future prices on their own. The moving average curves upward in a bullish trend and downward in a bearish trend. It is more reliable when used in conjunction with candlestick patterns.

Common Mistakes

Confusing periods with time units: The calculator defaults to using closing prices, but some users mistakenly use opening or high prices, altering the meaning of the moving average. Please verify the type of price entered.
Insufficient data points: A period of n requires at least n data points; entering fewer will result in an error.
Ignoring price adjustments: Futures experience contract rollovers and price gaps, requiring continuous contract prices to be adjusted. This tool uses raw prices and does not automatically adjust them.
Using short-term MAs to predict long-term trends: The 5-day moving average is highly volatile and should not be used directly to determine quarterly trends.
Making decisions based on a single MA value: A single moving average data point has limited significance. You should observe the direction of the moving average and its relative position to price changes.

Frequently Asked Questions (FAQ)

What is the ideal period for a moving average?: Short-term trading commonly uses 5, 10, or 20 days; medium-term uses 60 or 120 days; long-term uses 200 days or more. Adjust according to your trading style. This tool supports any positive integer period.
How should I use the calculated moving average value?: If the price is above the moving average and the moving average is trending upward, it can be considered a bullish signal; conversely, it is bearish. However, this should be confirmed with trading volume and chart patterns, and not relied upon exclusively.
Why does my input return an "At least N data points required" error?: Because the period cannot be greater than the number of input data points. For example, if you select a period of 10, you must enter at least 10 prices.
Can the tool calculate the Exponential Moving Average (EMA)?: The current version only supports the Simple Moving Average (SMA). EMA requires additional weighting parameters and may be added in the future.
Futures have night trading sessions; how is candlestick data handled?: This tool uses the sequence of closing prices you input and does not automatically handle night session splits. If intraday data is needed, please provide a continuous time series yourself.
How do I identify moving average crossovers (golden cross/death cross)?: This tool only calculates a single moving average. To identify a golden cross (short-term crossing above long-term), you need to calculate two moving averages separately and manually compare the value changes.

Limitations and Boundaries

This tool only provides numerical calculations and displays of simple moving averages and does not constitute investment advice. For actual trading decisions, please consider market conditions, risk tolerance, and professional advice. Calculation results are based on the raw prices you input, without adjustments for contract rollovers or price gaps. Data precision is rounded to two decimal places and may differ slightly from professional trading software. This tool does not store your data; all calculations are performed locally in your browser.

You can now enter your own futures data into the calculator above, try moving average values under different periods, and observe the relative position changes between the price and the moving average.