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+---
+epic: 6
+story: 6.7
+title: "Rounding Functions"
+status: draft
+---
+
+## Epic 6 — Advanced Math & Functions
+**Goal:** Scientific, financial, and power-user math.
+
+### Story 6.7: Rounding Functions
+
+As a **CalcPad user**,
+I want rounding functions including natural-language "round to nearest" and standard floor/ceil/round,
+So that I can control numeric precision in my calculations.
+
+**Acceptance Criteria:**
+
+**Given** the user writes `round 21 up to nearest 5`
+**When** the engine evaluates
+**Then** the result is `25`
+
+**Given** the user writes `round 22 down to nearest 5`
+**When** the engine evaluates
+**Then** the result is `20`
+
+**Given** the user writes `round 23 to nearest 5`
+**When** the engine evaluates
+**Then** the result is `25` (standard rounding: 23 is closer to 25 than 20)
+
+**Given** the user writes `floor(3.7)`
+**When** the engine evaluates
+**Then** the result is `3`
+
+**Given** the user writes `floor(-3.2)`
+**When** the engine evaluates
+**Then** the result is `-4` (floor rounds toward negative infinity)
+
+**Given** the user writes `ceil(3.2)`
+**When** the engine evaluates
+**Then** the result is `4`
+
+**Given** the user writes `ceil(-3.7)`
+**When** the engine evaluates
+**Then** the result is `-3` (ceil rounds toward positive infinity)
+
+**Given** the user writes `round(3.456, 2)`
+**When** the engine evaluates
+**Then** the result is `3.46` (rounded to 2 decimal places)
+
+**Given** the user writes `round(3.456, 0)`
+**When** the engine evaluates
+**Then** the result is `3`
+
+**Given** the user writes `round(2.5)`
+**When** the engine evaluates
+**Then** the result is `3` (round half up, or the chosen rounding convention is documented)