All lessons
Build POC and value area one row at a time
Let us calculate the lines ourselves, so the indicator stops feeling like a black box.
Calculate a small value area and explain why another platform can draw different boundaries.
Choose a fixed interval and row size, then apply a declared rule to find POC, VAH and VAL.
A session is a defined time window, not a universal setting. Record its start, end, timezone and any daylight-saving rule. Also record row size and feed. A full electronic session, a shorter trading window and a visible-screen range can contain different data.
POC, or Point of Control, is the row with most measured volume. VA, or Value Area, is a selected contiguous group around it. VAH means Value Area High and VAL means Value Area Low. The familiar 70% is a chosen historical-volume target, not a forecast probability.
Here is our teaching algorithm, not a universal platform rule. Start at POC; if POCs tie, choose the lower-priced row. Compare the next adjacent row above and below the included group, add the larger one, and repeat until included volume is at least 70% of total. For equal candidates choose the lower price; when only one side remains, use it. Include whole rows, so the result may exceed 70%.
Different algorithms can stop before exceeding a target, add pairs of rows or use different tie rules. The resulting boundaries may differ even on similar data. State the method before comparing screenshots, and freeze the interval before evaluating an idea.
Let’s work through it
- Freeze the time window, feed and row size.
- Find POC and write 70% of total as the target.
- Add rows using the declared comparison and tie rules; label VAL and VAH.
Let’s use numbers · hypothetical example
At prices 100–104 the volumes are 10, 25, 40, 20 and 5: total 100. POC 102 contributes 40. Add 101 with 25, reaching 65; then add 103 with 20, reaching 85. Our 70% target is met: VAL 101 and VAH 103 enclose 85 units.
Easy mistakes to watch for
- Expecting whole price rows to add to exactly 70%.
- Comparing values from different sessions or row sizes.
- Calling 70% a chance that the next price stays inside.
Keep in mind
These boundaries summarize past measured activity; they are not automatic entry, exit or valuation instructions.
Your turn
Change the two candidate volumes to a tie and apply our lower-price rule. Then explain how a different tie rule could change the result.
A quick check before we move on
How much volume is inside our final value area?
- 65 units
- 85 units
- 70 units exactly
Check answer
85 units 40 + 25 + 20 = 85. Our disclosed rule adds whole rows until at least 70 units are included.
Sources and further reading
- www.sierrachart.com/index.php
- www.tradingview.com/support/solutions/43000502040-volume-profile-indicators-basic-concepts/
Content reviewed: 29 October 2026
Educational material with hypothetical examples. Trading can cause substantial losses. A course, pattern, stop order or past result cannot guarantee a profit or limit every loss. Practise in simulation and check current rules and product terms in your jurisdiction.
