This page explains the CalSTRS calculator. The rules it uses are in plain English on the age factor, early retirement and payment options pages.
- 1
Find your benefit structure
Your first hire date puts you in CalSTRS 2% at 60 (hired by Dec. 31, 2012) or CalSTRS 2% at 62. A checkbox covers the cases on p. 18 that keep later hires in CalSTRS 2% at 60.
Handbook p. 18, Your benefit structure - 2
Project your service
We add the time from today to your retirement date to the service credit you enter, one year per year, plus any unused sick leave you enter.
Our assumption (see below) - 3
Find your age factor
We take your age in years and months on the last day of your retirement month and look it up in the handbook's age factor table. In 2% at 60 we add the career factor with 30+ years.
Handbook p. 78, Age factor tables: Age factor: CalSTRS 2% at 60 - 4
Apply the formula
Age factor × service credit × monthly final compensation, plus any longevity bonus. Final compensation is capped at the 2025-26 limit for your structure.
Handbook p. 54, Your retirement benefit - 5
Check eligibility
We test your age and service on the retirement date against your structure's rules, including concurrent retirement if you tick that box.
Handbook p. 20, Eligibility for benefits - 6
Show payment options
Option factors come from the handbook's sample tables. Between the printed ages we estimate, and label the result.
Handbook p. 82, Service retirement option factor tables
What the calculator doesn't cover
- Your final compensation. We use the number you enter. CalSTRS figures it from your records, with its own rules on what pay counts.
- Disability retirement, reinstatement after two or more years, and the Defined Benefit Supplement lifetime annuity.
- The cost of a redeposit, and survivor benefits for your own case (we show the handbook's examples).
- Taxes, health premiums or other deductions from your check.
- The federal 415(b) benefit limit, and pay caps or earnings limits newer than 2025-26.
- Exact option factors. CalSTRS uses exact ages and current factors.
Assumptions you should know
The "work longer" comparison keeps your final compensation the same, as the handbook's own examples do. The retirement date you enter is the day your benefit starts. Ages use the last day of your retirement month, the way the handbook's tables do.
How we check the math
The calculator runs on a small engine that reads every rule from one data file, with a handbook page cite for each rule. Automated tests check it against the worked examples printed in the handbook. They run every time the site is built.
| Handbook example | Handbook | Our engine | Page |
|---|---|---|---|
| Faye, now at 58 | $3,317.60 | $3,317.60 | p. 66 Match |
| Faye, at 60 | $4,443.00 | $4,433.00 | p. 66 See below |
| Faye, at 62 | $5,148.00 | $5,148.00 | p. 66 Match |
| Manuel, at 62 | $3,840.00 | $3,840.00 | p. 66 Match |
| Manuel, at 65 | $5,040.00 | $5,040.00 | p. 66 Match |
| Mariana | $3,168.00 | $3,168.00 | p. 63 Match |
| Angela, Member-Only | $3,192.92 | $3,192.92 | pp. 75-76 Match |
| Angela, 100% Beneficiary Option | $2,883.53 | $2,883.53 | pp. 75-76 Match |
| Angela, 75% Beneficiary Option | $2,971.33 | $2,971.33 | pp. 75-76 Match |
| Angela, 50% Beneficiary Option | $3,048.92 | $3,048.92 | pp. 75-76 Match |
| Compound Option | $2,975.80 | $2,975.80 | p. 77 Match |
| Jaime, Reduced Benefit Election | $1,250.00 | $1,250.00 | p. 45 Match |
| Miriam, before redeposit | $2,660.00 | $2,660.00 | p. 59 Match |
| Miriam, after redeposit | $4,730.00 | $4,730.00 | p. 59 Match |
| Anthony, 1 year of permissive service | $9,400.00 | $9,850.00 | pp. 60-61 See below |
| Ricardo, reinstated | $2,770.00 | $2,770.00 | p. 95 Match |
| Michelle, reinstated | $2,544.00 | $2,544.00 | p. 96 Match |
| Earnings over the limit | $9,755.00 | $9,755.00 | p. 92 Match |
| Rob, Coverage A | $2,954.00 | $2,954.00 | p. 101 Match |
| Sharon, spouse later | $306.32 | $306.32 | pp. 104-105 Match |
| Sanjay, after retirement | $7,763.00 | $7,763.00 | p. 106 Match |
| Supplement, 3-year payout | $615.58 | $615.58 | p. 86 Match |
Things to check with CalSTRS
The handbook doesn't settle these points, or disagrees with itself. Each is labeled where it shows up on the site. Here's what we do about each one.
The handbook's example says Anthony, a 31-year-old 2% at 62 member, pays 18.8% of his pay to buy one year: $9,400 on $50,000. The rate table on the next page shows 19.7% for age 31, which would be $9,850.
We use the table.
Handbook p. 60, Cost to purchase permissive service creditThe handbook's example says Faye would get $4,443.00 a month at 60. Its own numbers (2.2% x 31 years x $6,500) come to $4,433.00.
We use the formula, so we show $4,433.00.
Handbook p. 66, Your retirement formula: How it worksIn Miriam's example the handbook rounds 35.9 months to 3.00 years; it is closer to 2.99.
We show the months: 35.9.
Handbook p. 59, Approximate time to recover costsThe handbook's text says the age factor drops 0.01% for each month you retire before normal retirement age. But its 2% at 60 table drops only 0.005% a month between ages 50 and 55.
We use the table.
Handbook p. 78, Age factor tablesThe handbook says your age factor uses your age at the end of your retirement month. It doesn't say whether the age-55 (or 50) test works the same way.
We use your actual age on your retirement date, the stricter reading.
Handbook p. 44, Choosing your retirement dateIf you were born on the 29th, 30th or 31st, the handbook doesn't say how a shorter month is counted.
We count your birthday month as a full month.
Handbook p. 78, Age factor tablesThe handbook prints option factors only for sample ages (member 55 to 70, beneficiary every 5 years from 20 to 70), and CalSTRS updates them from time to time.
Between sample ages we estimate the factor and label it as an estimate.
Handbook p. 82, Service retirement option factor tablesFor members who return to work for two years or more, the handbook uses an 'adjusted age factor' but doesn't explain how it's worked out.
We don't estimate this case.
Handbook p. 96, Reinstate for two years or moreThe longevity bonus table lists 30, 31 and 32+ years. The handbook says the bonus is 'partially reduced' if you choose an option, but doesn't show how.
We read the bands as whole years and reduce the bonus by the same option factor as the rest of your benefit.
Handbook p. 67, Longevity bonusFor the Reduced Benefit Election the handbook doesn't say whether the career factor is included in the 'as if you were 60' amount.
We include it when you have 30+ years.
Handbook p. 45, Reduced Benefit ElectionThe handbook gives the 2025-26 pay caps and earnings limit only. Newer figures are posted by CalSTRS.
We use the 2025-26 figures.
Handbook p. 122, Compensation cap under IRC and California Education CodeContribution rates shown are for 2025-26; the 2% at 62 rate can change.
We show them as 2025-26 rates.
Handbook p. 21, ContributionsThe handbook describes the purchasing power level two slightly different ways and doesn't give the payment formula.
We describe it but don't calculate it.
Handbook p. 93, Purchasing power protectionSurvivor examples use CalSTRS factors that aren't printed in the handbook's tables.
We show the examples but don't calculate survivor benefits for you.
Handbook p. 105, Coverage B survivor benefit example (continued)The handbook says redeposit interest is 'currently 7%', but its own example costs less than 7% a year would.
We don't estimate redeposit costs. Ask CalSTRS for a bill.
Handbook p. 27, Cost to redepositThe federal benefit limit is given only for age 60.
We don't apply it in the calculator.
Handbook p. 122, Section 415(b) limitLifetime annuity factors for the Defined Benefit Supplement aren't in the handbook.
We calculate only the 3-to-10-year payout.
Handbook p. 84, Defined Benefit Supplement annuity calculation estimatesTo find your earliest and full-benefit dates we assume you earn one full year of service each year.
Part-time work would push those dates later.
Handbook p. 55, How service credit is calculatedThe handbook doesn't say whether bought (permissive) service counts toward the 30 years for the career factor.
We count it.
Handbook p. 79, Career factorWe cover only the basic disability rule.
We don't calculate disability benefits.
Handbook p. 9, CalSTRS programs at a glanceSource
- CalSTRS Member Handbook 2026 edition (Jan. 1, 2026 - June 30, 2027)
Page numbers are the handbook's printed page numbers. "Cover insert" is the update sheet at the front of the handbook. Last reviewed Nov. 12, 2026.
Source: CalSTRS Member Handbook, 2026 edition (Jan. 1, 2026 - June 30, 2027), pp. 9, 18, 20, 21, 27, 44, 45, 54, 55, 59, 60, 66, 67, 78, 79, 82, 84, 93, 96, 105, 122. Last reviewed .