Calculate social return on investment (SROI) from investment, yearly outcome value and years, with optional deadweight, attribution and discounting.

Include money and monetized time or labor once.

Before the deductions and discounting entered below.

Adjustments and discounting
Share that would occur without the project. Blank = 0%.

Share attributed to other contributors. Blank = 0%.

Share offset by reduced outcomes elsewhere. Blank = 0%.

Reduction in remaining outcome after year one. Blank = 0%.

3.5% is the standard rate in the SROI Guide (UK Green Book). Blank = 0%.

Related Calculators

SROI Formula

The calculator reports benefit-cost SROI as the present value of adjusted outcomes divided by upfront investment or an already discounted investment cost total. It multiplies year-one gross outcome value by the retained fractions after deadweight, attribution to others and displacement. Later years compound the annual drop-off after year one; each yearโ€™s outcome is valued at year end and discounted to the investment date. All amounts must use consistent USD values, and already discounted outcome values must not be discounted again. The formula below is the simpler one-period special case with no deductions or discounting. Monetized time or labor belongs in total investment and must not be counted twice.

SROI & = (TV + ITV) / (M + TC)\ TC & = T ร— R

Variables:

  • SROI is the benefit-cost ratio, or social value per dollar invested. Net SROI instead subtracts investment from benefits before dividing by investment; net SROI equals the benefit-cost ratio minus one.
  • TV is the tangible value to the community ($)
  • ITV is the intangible value to the community ($), expressed in monetary terms
  • M is the total amount of money spent ($)
  • TC is the monetized time/labor cost ($)
  • T is the total time invested (hours, or workdays if you convert days to hours)
  • R is the labor rate ($ per hour)

For this one-period special case, add tangible and monetized intangible community value and divide by total investment, including any monetized time or labor cost. For the multi-year calculator, enter the gross year-one outcome value, duration and evidence-based adjustments instead. The outcome-target mode solves for the year-one value needed for a positive target ratio; the investment mode solves the largest upfront investment compatible with that target under the entered assumptions.

How to Calculate SROI?

The following steps outline the one-period special case. In the calculator, combine all investment costs into Total investment (USD) and enter the combined outcome value as Gross year-one outcome value (USD). Set duration to one year and all adjustment and discount rates to zero to reproduce this case.

  1. First, determine the tangible value to the community (TV) and the intangible value to the community (ITV), and express both in dollars ($).
  2. Next, determine the total amount of money spent (M) ($). 
  3. If including time in the investment, determine the total time invested (T) and the labor rate (R), then calculate the monetized time cost: TC = T ร— R.
  4. Next, gather the formula from above: SROI = (TV + ITV) / (M + TC).
  5. Finally, calculate the SROI.
  6. After inserting the variables and calculating the result, check your answer with the calculator above. 

Example Problem:

This one-period example uses total investment of USD 20,600, gross year-one outcome value of USD 50,000, duration of one year, and zero deadweight, attribution, displacement, drop-off and discount rates. It produces approximately 2.4272:1 benefit-cost SROI and 1.4272 net SROI. These are illustrative values, not suggested assumptions.

tangible and intangible value to the community ($) = 50,000

total time invested = 3 days (assume 8-hour workdays)

labor rate ($/hour) = 25

total amount of money spent ($) = 20,000

SROI = (TV + ITV) / (M + TC) = 50,000 / (20,000 + (3 ร— 8 ร— 25)) = 50,000 / 20,600 = 2.4272

Outcome valuations, deadweight, attribution, displacement and duration require evidence. This arithmetic model does not establish causation or validate financial proxies. Avoid double counting overlapping outcomes or inputs. Sensitivity scenarios vary selected assumptions only, and ratios from different projects should not be ranked without comparable scope and valuation methods.