Portfolio Return Calculator
The formula
What the portfolio return tells you
The one-period weighted blend of asset returns — arithmetic is all it takes. The real lesson is attribution: which slice of the pie actually produced (or destroyed) the number.
Calculation: Rp = Σ wi × Ri (weights must total 100%). Enter your inputs and every substitution is shown below the result.
Reading the result
Compare weighted vs equal-weighted results shown here: if they differ a lot, your sizing decision, not the assets, drove the outcome. That is the whole discipline of allocation in one line.
Rules of thumb: Check weight sums before every review: drift from rebalancing discipline is where most "unexpected" returns hide
Limitations and best practice
This is a single-period blend. Multiperiod compounding is different — volatility drag means the geometric return runs below the arithmetic average by roughly σ²/2 each year.
This calculator gives an estimate based on standard formulas; it is not professional financial, medical, legal or engineering advice. Verify anything you plan to act on with a qualified professional and your own records.
Frequently asked questions
Why is my realized return lower than the weighted average?
Arithmetic or geometric average for multi-year?
Source & methodology
Standard portfolio mathematics; see Elton et al., "Investments: Portfolio Analysis, Performance and Management".
Portfolio Return: the number, the method and the caveats
Capital decisions deserve better than a gut feeling — this page gives you the arithmetic to defend one. Searchers land on a Portfolio Return page for three reasons — to plan, to compare options, and to check that somebody else’s arithmetic is honest. This tool serves all three, and everything after the calculator explains the model instead of hiding it.
In Investing & Markets the same quantity is often quoted under two or three different conventions. The formula printed above fixes one convention and applies it consistently, which is what makes results from this page comparable with each other.
It helps to separate the mechanics from the interpretation. The mechanics are fixed: Rp = Σ wi × Ri (weights must total 100%). Anyone, anywhere, entering the same inputs will get the same 7.50 %. The interpretation is where experience counts: whether 7.50 % is good, normal or alarming depends on comparisons covered below, and that is the part most articles about Portfolio Return never explain.
Nothing below is stock text pasted around a number: the worked example computes weighted portfolio return = 7.50 % from this tool’s own defaults, and the sensitivity section ranks the inputs that move the result — Asset A return first, at ≈9.1 % of the headline for a ten-percent error either way in that input — which is the thread the rest of this guide pulls on.
The Portfolio Return formula, explained
The engine implements a single stated model: Rp = Σ wi × Ri (weights must total 100%). There is no hidden coefficient and no login-gated precision — the formula printed is the formula executed, which is also what makes the result citable.
Asset A weight (%) (example value 115) is a numeric input whose unit is fixed by the label; a wrong unit is a wrong answer wearing a plausible disguise. Enter it exactly as your document states it — quoted annual, monthly and effective rates are three different numbers.
Asset A return (%) (example value 10) is a numeric input whose unit is fixed by the label; a wrong unit is a wrong answer wearing a plausible disguise. Enter it exactly as your document states it — quoted annual, monthly and effective rates are three different numbers.
Asset B weight (%) (example value 35) is a quantity rather than a category — precision here is cheap and worth having. Check the convention first: if the source says “6.5 % per year”, type 6.5 and let the formula do the rest.
Asset B return (%) (example value 5) is a plain measured quantity — the unit shown in the label is the unit the formula expects. Enter it exactly as your document states it — quoted annual, monthly and effective rates are three different numbers.
Asset C weight (%) (example value 19) is a measured number in the unit named by the label; the formula does not convert for you. Rates are the most mis-transcribed input on any page like this; copy it from the document rather than retyping from memory.
Asset C return (%) (example value -3) is a numeric input whose unit is fixed by the label; a wrong unit is a wrong answer wearing a plausible disguise. Enter it exactly as your document states it — quoted annual, monthly and effective rates are three different numbers.
Portfolio Return with real numbers, step by step
Rather than describe the calculation, here it is end to end — every substitution in order, starting from the inputs above. Starting figures: Asset A weight (%), Asset A return (%), Asset B weight (%), Asset B return (%). The endpoint of that chain is 7.50 % of weighted portfolio return, sitting in the “Weights sum to 169.0% — normalized for you; check the inputs” band.
- Σ wᵢrᵢ = 115×10 + 35×5 + 19×-3 = 1268.0 (percent-weights)
- ÷ total weight 169% → 7.50%
Contribution from A — 6.80 %. Compare it against the main result of 7.50 % before drawing conclusions.
Contribution from B — 1.04 %. Compare it against the main result of 7.50 % before drawing conclusions.
Contribution from C — -0.34 %. This is the number experienced users quote when the headline alone would mislead.
Simple (unweighted) average — 4.00 %. Read next to the headline, this is the figure that shows the shape of the trade-off.
Re-running with your own figures is instant; re-running by hand once is the best way to know the tool is telling you the truth.
Scenario table: Portfolio Return at ±10 % and ±20 % of the key input
Read this table as the practical error bar on the headline figure. It answers the question people actually have after seeing a single number: how wrong could this be if the main input is off by ten or twenty percent?
| Asset A return setting | Weighted portfolio return |
|---|---|
| 80 % of the example value | 6.14 % |
| 90 % of the example value | 6.82 % |
| example inputs | 7.50 % |
| 110 % of the example value | 8.18 % |
| 120 % of the example value | 8.86 % |
The corridor runs from 6.14 % to 8.86 % across that band — which is the range worth planning inside rather than the single 7.50 % point estimate. Reproduce it in the form above by editing Asset A return alone; the substitution steps will follow your figures exactly.
The levers behind Portfolio Return, ranked by effect
Generic advice says “it depends on your inputs”; this section says exactly how much. Each field was perturbed by ±10 % in isolation and the weighted portfolio return recomputed, so the ranking below is measured rather than asserted. For Portfolio Return the ranking is measured rather than guessed, and it belongs to these defaults: shift the starting point and the order can shift with it.
- Nudge Asset A return by ±10 % and Portfolio Return lands between 6.82 % and 8.18 % (sensitivity ≈9.1 %)
- Nudge Asset A weight by ±10 % and Portfolio Return lands between 7.32 % and 7.66 % (sensitivity ≈2.4 %)
- Nudge Asset C weight by ±10 % and Portfolio Return lands between 7.39 % and 7.62 % (sensitivity ≈1.6 %)
- Asset B return: ten percent up gives 7.61 %, ten percent down gives 7.40 % — ≈1.4 % of the weighted portfolio return either way
- Nudge Asset B weight by ±10 % and Portfolio Return lands between 7.45 % and 7.56 % (sensitivity ≈0.7 %)
- Asset C return +10 % → Portfolio Return = 7.47 % · −10 % → 7.54 % (the weighted portfolio return shifts ≈0.4 %)
Asset A return is the dominant lever here: ten percent either way moves the result by about 9.1 %, from 6.82 % to 8.18 %. That is where a careless figure does the most damage, so check it against a source, and treat Asset A weight as the second priority (≈2.4 % per ten percent). The rest of the inputs earn only a rounding-error of attention, and that asymmetry is the practical payoff of measuring rather than asserting.
What a Portfolio Return of 7.50 % means in practice
A number on its own is trivia; a number against a range is intelligence. On the example inputs the band reads “Weights sum to 169.0% — normalized for you; check the inputs”; your own figures place you on a different rung of the same ladder. The sensitivity list shows how far a modest input error moves you along that ladder: for Asset A return, ±10 % covers 6.82 % to 8.18 %. The practical reading rules: read the band as a starting hypothesis, then test it: change the two dominant inputs by ten percent and see whether the verdict survives. Verdicts that survive stress are the ones worth acting on.
Where Portfolio Return sits next to similar measures: this tool answers “how much is the Portfolio Return”, while the related calculators answer “what do I do about it”. Reading the result alone tends to over-weight a single snapshot; pairing it with the companion tools above turns the number into a decision.
The errors that quietly break a Portfolio Return figure
This is a single-period blend. Multiperiod compounding is different — volatility drag means the geometric return runs below the arithmetic average by roughly σ²/2 each year. This calculator gives an estimate based on standard formulas; it is not professional financial, medical, legal or engineering advice. Verify anything you plan to act on with a qualified professional and your own records.
Reusing a Portfolio Return from last season. In Investing & Markets the inputs are the thing that drifts; the formula does not.
This model has its own particular trap: Asset A return carries ≈9.1 % of the response per ten percent of error, so effort spent elsewhere is largely decorative.
Another is comparing across contexts: a Portfolio Return computed with one set of conventions should never be lined up against a figure computed with another. Check the inputs behind both before ranking them.
Portfolio Return verification checklist
- Confirm the example values are plausible for your own situation before replacing them.
- State, in one sentence, which convention each rate, unit or period in the form is using.
- Check Asset A return before anything else: it is the measured dominant input, ≈9.1 % of Portfolio Return per ten percent.
- Recompute once with the dominant input deliberately set low, and see whether the decision changes.
- Check that every field the formula needs actually arrived from a document, not from recollection.
- Repeat the ±10 % test on the inputs that matter and see whether the decision — not just the number — still holds.
Step by step: getting a trustworthy Portfolio Return out of this tool
The tool does the arithmetic; the routine below is what makes the arithmetic trustworthy. Five steps, a minute total — and afterwards you will know not just what the number is, but which assumption produced it.
Step 1 — gather before you type. Portfolio Return depends on asset a weight (%), asset a return (%), asset b weight (%), asset b return (%), asset c weight (%), asset c return (%). Collect them from a source document — a statement, a report, an invoice, a log — rather than from memory, because recalled inputs are the single largest cause of wrong results. If the answer changes your behaviour, it deserves a second run with different assumptions.
Step 2 — enter the conservative case first. Resist the flattering scenario. Type the inputs you would defend in front of a sceptical reader, read the Weighted portfolio return (7.50 % for the example values), and note the verdict band. Re-running a number costs seconds; retracting a decision costs considerably more.
Step 3 — isolate your variables. Change one field, observe, revert. The live sensitivity list does the ranking for the default inputs; verify it against your own, because dominance shifts when the starting point shifts. The fastest sanity test is to guess the answer first and see how far the calculation disagrees.
Step 4 — compute a corridor, not a point. Three runs — worst, likely, best — turn Portfolio Return from a snapshot into a range. Plan against the pessimistic end and treat the optimistic end as the upside story. Most surprises in numbers are surprises about inputs, not about formulas.
Step 5 — save the story with the figure. A number without its inputs and its date is unusable within a quarter. Record 7.50 %, the assumptions behind it, and today’s date; your future self will be auditing a stranger’s arithmetic. The input you reach for first is usually the one you measured longest ago.
The real-world conversations Portfolio Return settles
Investing & Markets arguments end at arithmetic or they do not end. Portfolio Return is the arithmetic: 7.50 % on the example inputs, reproducible by anyone who types the same numbers. Note the assumption you are least sure about; that is where the real risk lives.
The audience for this page is investors and founders comparing opportunities on equal terms. In professional Portfolio Management practice the pattern is always the same — screen with Portfolio Return, then invest slow analysis only in whatever survives the screen. Write the assumptions in the same file as the result, and future arguments take minutes instead of meetings.
Re-running this page costs nothing and catches the slow drifts that never announce themselves. In Investing & Markets the expensive mistakes are rarely sudden; they are small changes in Asset A weight (%) that nobody recalculated for a year. One decimal place more than your data supports is one decimal place of fiction.
Portfolio Return — frequently asked questions
What affects Portfolio Return the most?
The short answer: Asset A return. The longer answer is the sensitivity table on this page, where every numeric input was probed by ten percent and the weighted portfolio return recalculated — Asset A return moved it furthest, by roughly 9.1 % (6.82 % to 8.18 %).
Which matters more: asset a weight or asset a return?
By the numbers, Asset A return: a ten-percent change in it moves the result ≈9.1 %, versus ≈2.4 % for Asset A weight. Spend your measuring effort in that order — precision on the weaker lever buys almost nothing.
What is a typical Portfolio Return?
On the worked example above Portfolio Return comes out at 7.50 %. Treat that as one point on a distribution rather than a norm: the bands, the companion outputs and the sensitivity ranking tell you how wide the plausible range really is.
How do I calculate Portfolio Return by hand?
Rp = Σ wi × Ri (weights must total 100%) is the entire method. Work the inputs in that order — Σ wᵢrᵢ = 115×10 + 35×5 + 19×-3 = 1268.0 (percent-weights) — and you will reach 7.50 % on the default figures, the same number this tool prints.
What happens to Portfolio Return if asset a return changes by 10 %?
On these inputs a ±10 % change in asset a return takes Portfolio Return to 8.18 % against the 7.50 % example — around 9.1 % of the headline. The same test on every other field is in the sensitivity section.
Is the Portfolio Return result of 7.50 % good or bad?
Neither, on its own — the label “Weights sum to 169.0% — normalized for you; check the inputs” is the band this figure falls in for the example inputs, and your own inputs will place you elsewhere on the same ladder. Judge the number against your history and your alternatives, and remember that a ten-percent error in Asset A return alone moves it by ≈9.1 %.
What is a good Portfolio Return?
Markets give away free benchmarks: anything that beats the relevant index after costs earns the label "good", and this tool’s verdict band translates Portfolio Return against experience ranges. Before that, check that the inputs are realistic — a great Portfolio Return built on optimistic inputs is just a nicer-looking error.
What affects Portfolio Return the most?
Sensitivity depends on where you start, but the inputs Asset A weight (%) and Asset A return (%) typically move Portfolio Return further than the rest because they enter the formula multiplicatively. If you can only measure two things well, measure those and hold the others at conservative defaults.
Why is my realized return lower than the weighted average?
Because averaging assumes you rebalanced back to target weights each period. Buy-and-hold tilts toward whatever won, changing the effective weights.
Arithmetic or geometric average for multi-year?
Geometric — it is what you actually earned. Arithmetic only forecasts correctly for one-period bets without reinvestment.
Can this tool see the numbers I type?
It cannot. There is no submission step: the calculation happens in your browser and the result disappears when you close the page. Treat the fields above as a scratchpad rather than a form.
What the labels on this page mean
- Contribution from A
- 6.80 % for the Portfolio Return worked case; it sits next to the main result because it carries context the headline leaves out.
- Contribution from B
- 1.04 % for the Portfolio Return worked case; it sits next to the main result because it carries context the headline leaves out.
- Contribution from C
- -0.34 % on the example inputs — a companion figure printed beside the headline of Portfolio Return so that no result is read in isolation.
- Weighted portfolio return
- The primary output of this tool: 7.50 % for the default inputs, computed exactly from Rp = Σ wi × Ri (weights must total 100%).
- Worked example
- Every substitution in order, from the example inputs to 7.50 % — the audit trail for the headline figure.
- Verdict band
- The interpretation attached to a result (“Weights sum to 169.0% — normalized for you; check the inputs” on these inputs), which turns a bare number into a position on a scale.
- Sensitivity (±10 %)
- How far the Portfolio Return moves when a single input is nudged ten percent either way; the ranked list on this page is computed live from this engine.
Method, sources and what this tool cannot tell you
Everything above runs on one stated formula, applied without hidden coefficients: Rp = Σ wi × Ri (weights must total 100%). Source of record: Standard portfolio mathematics; see Elton et al., "Investments: Portfolio Analysis, Performance and Management". Any other implementation of this model should return the same figure for the same inputs. If one does not, the difference is in its assumptions — which this page prints and that one probably does not.
This page is an estimation aid, not professional advice. The design rule is simple: two people entering identical figures must get identical answers. The sensitivity table above is part of that promise rather than a bonus: it lets you see how much of the result depends on how carefully you measured.
After the number: what to do with it
Run the pessimistic case before the optimistic one; an opportunity that survives the pessimistic inputs is the only kind worth pursuing.
The audience here is investors and founders comparing opportunities on equal terms. Everything you need to defend the result — formula, substitution, sensitivity, source — is printed above, so the only remaining variable is the honesty of your inputs.