Calculate Social Security Disability
Use this interactive calculator to estimate a monthly Social Security Disability Insurance benefit using the Primary Insurance Amount formula, then subtract any workers’ compensation or other public disability offset. This is an educational estimator for SSDI, not an official Social Security Administration determination.
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Enter your information and click Calculate Disability Estimate.
How to calculate Social Security disability benefits the right way
When people search for how to calculate Social Security disability, they are usually trying to answer one of two questions: “Will I qualify?” and “How much might I receive each month?” The answer is more technical than many expect because Social Security Disability Insurance, usually called SSDI, is not calculated from a simple percentage of your last paycheck. Instead, the Social Security Administration looks at your covered earnings over time, indexes many of those earnings to account for wage growth, computes an Average Indexed Monthly Earnings amount called AIME, and then applies a legal benefit formula known as the Primary Insurance Amount or PIA formula.
This page focuses on that monthly benefit estimate. The calculator above uses the standard PIA bend-point structure that applies to disability and retirement benefit calculations. It then subtracts an optional workers’ compensation or other public disability offset to produce a net monthly estimate. That means the tool is useful for understanding the mechanics of SSDI, but it should never be treated as an official award notice. The Social Security Administration will still verify your earnings record, insured status, disability onset date, and any potential offsets before setting your actual benefit amount.
SSDI versus SSI: know which program you are estimating
Before you calculate anything, it is important to distinguish SSDI from Supplemental Security Income, or SSI. SSDI is an insurance program funded through payroll taxes. In general, you qualify based on your prior work and enough recent work credits. SSI is a needs-based program for people with limited income and resources who are aged, blind, or disabled. Because SSDI is based on your earnings history, the main calculation starts with your AIME. By contrast, SSI relies on federal benefit rates, state supplements in some places, living arrangements, and countable income rules.
If your goal is to estimate a monthly amount tied to your work history, you are almost certainly talking about SSDI. If you have little or no work record and are asking what a low-income disabled adult may receive, you are probably asking about SSI instead. Many people receive only one program, but some can qualify for both if their SSDI amount is low enough and they meet SSI’s non-medical rules.
The core SSDI formula in plain English
To calculate an SSDI payment estimate, Social Security generally follows these broad steps:
- Review your covered earnings record.
- Index prior earnings to national wage growth where required.
- Average those indexed earnings to reach your AIME.
- Apply the PIA bend-point formula to your AIME.
- Round according to Social Security rules.
- Reduce the benefit if a workers’ compensation or public disability offset applies.
The part most people can estimate themselves is the final formula once they know or approximate their AIME. For 2025, the standard PIA formula uses these bend points: 90 percent of the first $1,226 of AIME, plus 32 percent of AIME over $1,226 through $7,391, plus 15 percent of AIME over $7,391. This creates a progressive benefit structure where lower portions of earnings are replaced at a higher rate than higher portions.
| 2025 PIA bend-point bracket | Formula rate | What it means |
|---|---|---|
| First $1,226 of AIME | 90% | The first slice of your indexed monthly earnings is replaced at the highest rate. |
| $1,226 to $7,391 of AIME | 32% | The middle slice is replaced at a moderate rate. |
| Above $7,391 of AIME | 15% | The top slice is replaced at the lowest rate. |
Suppose your AIME is $4,200. The estimate would work like this. First, take 90 percent of $1,226, which is $1,103.40. Then subtract $1,226 from $4,200, leaving $2,974 in the second bracket. Take 32 percent of $2,974, which is $951.68. Because the AIME does not exceed $7,391, there is no third bracket amount. Add the pieces together and you get $2,055.08. Under Social Security’s standard rounding convention, the PIA is generally rounded down to the next lower dime, which would be $2,055.00. If you also receive a $350 monthly offset from workers’ compensation or another public disability payment that triggers reduction rules, your net estimate becomes $1,705.00.
Why your estimate may differ from your official Social Security number
Even if you apply the formula carefully, your estimate can still differ from Social Security’s official result. That does not mean your math is wrong. It usually means the agency has more precise information than you do. The most common reasons include an inaccurate earnings history, uncertainty about your disability onset date, a period of low or zero earnings, military or non-covered employment issues, or misunderstanding whether a state or federal disability payment counts as an offset source.
Another major issue is insured status. You can be medically disabled and still not qualify for SSDI if you have not earned enough recent work credits. In many cases, adults over age 31 need at least 20 work credits in the 10 years before disability onset, although the rules are somewhat different for younger workers. That is why calculating the monthly amount is only one part of the larger disability eligibility picture.
Work credits and current earnings still matter
A surprising number of applicants focus only on the expected monthly payment and forget about current work activity. Social Security uses a concept called Substantial Gainful Activity, or SGA, to evaluate whether your earnings are too high for disability purposes. The threshold changes over time and is higher for claimants who are blind under the program’s statutory standard.
| 2025 Social Security disability thresholds | Monthly or annual amount | Why it matters |
|---|---|---|
| SGA, non-blind | $1,620 per month | Earnings above this level can affect initial SSDI eligibility. |
| SGA, blind | $2,700 per month | Higher earnings limit for claimants who meet blindness rules. |
| Trial work month amount | $1,160 per month | Used in post-entitlement work incentive tracking. |
| Quarter of coverage amount | $1,810 in yearly earnings per credit | Determines how work credits are earned for insured status. |
| SSI federal benefit rate, individual | $967 per month | Helpful comparison if a person may also be eligible for SSI. |
If you are earning above SGA, Social Security may decide that you are not disabled for SSDI purposes regardless of the formula result shown by an estimator. That is why the calculator on this page displays both the benefit estimate and a message comparing your current earnings to the relevant SGA level. It helps you separate the monthly amount question from the eligibility question.
A step-by-step example of how to calculate social security disability
Here is a simple walkthrough you can follow manually if you want to check the calculator:
- Find or estimate your AIME. If you do not know it, review your Social Security earnings statement or use your best earnings-based estimate.
- Apply the first bracket: multiply the first $1,226 of AIME by 0.90.
- Apply the second bracket: if your AIME is above $1,226, multiply the amount between $1,226 and $7,391 by 0.32.
- Apply the third bracket: if your AIME is above $7,391, multiply the amount over $7,391 by 0.15.
- Add the three bracket results together.
- Round down to the next lower dime.
- Subtract any valid monthly workers’ compensation or public disability offset.
- Compare your current monthly work earnings to the SGA threshold for your blindness status.
That process gives you a practical estimate. It is not a complete legal analysis, but it is the most direct way to understand how monthly SSDI benefits are derived from a work-based earnings record.
Common mistakes people make when estimating SSDI
- Using gross annual salary instead of AIME. The formula does not run on your current yearly pay alone.
- Confusing SSDI with SSI. The programs use different financial rules and payment methods.
- Ignoring work credits. A person can be disabled and still not be insured for SSDI.
- Ignoring SGA. High current earnings can prevent approval even if the formula suggests a strong benefit amount.
- Forgetting offsets. Workers’ compensation and certain public disability benefits can reduce the final check.
- Assuming an online estimate is official. Only Social Security can issue the final determination.
How age, onset date, and work history affect the estimate
Although the PIA formula itself is straightforward once you know your AIME, the path to that AIME depends heavily on age and work history. Younger workers may need fewer credits to qualify, but they also may have fewer years of earnings, which can limit the monthly benefit amount. Workers with long, steady, well-documented earnings histories usually have more predictable estimates because their AIME is easier to verify. Disability onset date matters because it can affect which earnings years count, whether enough recent work credits are present, and whether you remained insured when you became disabled.
For example, someone who became disabled at age 35 after a decade of covered work may have enough credits but still receive a lower monthly amount than someone who became disabled at age 55 after decades of high taxable earnings. The younger worker’s calculation can be perfectly valid, but there may be fewer high-earning years in the record. In contrast, a higher earner with a long career may cross further into the second and third PIA brackets, producing a larger benefit estimate.
What this calculator does and does not do
This calculator is designed to estimate SSDI from the PIA formula and show a simple visual of gross benefit, offset, and net benefit. It does not recreate Social Security’s full earnings indexing process, determine medical disability, verify whether you are insured, evaluate family benefits, compute dependent benefits for children, or apply every possible legal exception. It also does not calculate attorney fees, tax consequences, Medicare waiting periods, or state-specific supplement rules. Those topics can be important, but they are separate from the core monthly SSDI estimate.
Where to verify your estimate with official sources
The best way to verify your own estimate is to compare it against official Social Security materials and your personal Social Security account. The SSA provides detailed explanations of disability benefits, bend-point formulas, and SGA amounts. For authoritative reference, review the official SSA disability benefits overview at ssa.gov/benefits/disability, the PIA formula explanation at ssa.gov/oact/cola/piaformula.html, and the annual SGA thresholds at ssa.gov/oact/cola/sga.html. These are the best places to confirm current figures because Social Security updates them periodically.
Best practices before you file a disability claim
- Download and review your earnings history for missing years or incorrect wages.
- Identify your likely disability onset date and gather medical evidence supporting it.
- Estimate your current earnings to see whether SGA may be an issue.
- List any workers’ compensation or public disability payments that may reduce SSDI.
- Understand whether you might also qualify for SSI if your SSDI amount is low.
- Keep records of all communication, applications, appeal deadlines, and supporting documents.
Bottom line
If you want to calculate Social Security disability benefits, the most important number is your AIME. Once you have that number, the SSDI estimate comes from applying the bend-point formula, rounding properly, and then accounting for any offsets. That tells you the likely monthly payment range. Next, you must check whether you are insured for disability benefits and whether your current work activity exceeds the applicable SGA threshold. In other words, the monthly estimate and the legal eligibility analysis work together. One answers “how much,” while the other answers “can I receive it at all?”
Use the calculator above to build a fast, structured estimate. Then compare your result against official SSA guidance and your earnings record. That combination gives you the clearest picture of what your Social Security disability benefit may look like and what issues could still change the final award.