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Wells Score Calculator (Pulmonary Embolism)

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Calculate the Wells clinical prediction score for pulmonary embolism, with both the three-tier and simplified two-tier probability interpretations shown.

Reviewed by the thecalcu.com team · Last updated July 10, 2026

Clinical Signs and Symptoms of DVT (3 pts)

PE Is #1 Diagnosis or Equally Likely (3 pts)

Heart Rate > 100 bpm (1.5 pts)

Immobilization ≥3 Days or Surgery in Previous 4 Weeks (1.5 pts)

Previous Objectively Diagnosed PE or DVT (1.5 pts)

Hemoptysis (1 pt)

Malignancy Treated Within 6 Months, or Palliative (1 pt)

Wells Score

0

Three-Tier Probability

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Two-Tier Probability

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Not a substitute for clinical judgment. The Wells score informs, but does not replace, the full PE workup pathway (D-dimer, imaging) determined by a qualified healthcare provider.

What is a Wells Score (PE)?

The Wells Score Calculator computes the Wells clinical prediction rule for pulmonary embolism (PE), a validated tool that estimates pretest probability from seven weighted criteria: clinical signs of DVT, PE being the most likely diagnosis, tachycardia, recent immobilization or surgery, prior PE or DVT, hemoptysis, and active malignancy.

Select yes or no for each criterion to see your total score along with both the original three-tier (low/moderate/high) and the simplified two-tier (PE unlikely/PE likely) interpretations. For a complementary PE probability tool using only objective variables, see the Revised Geneva Score Calculator; for a very-low-risk rule-out tool, see the PERC Calculator.

Why Use a Wells Score Calculator?

Manually tallying seven criteria with uneven point values (3, 1.5, and 1 point items mixed together) is easy to miscalculate under time pressure. This calculator handles the arithmetic instantly and shows both standard interpretations of the resulting score side by side.

It's a useful reference for reviewing how each individual criterion contributes to the overall probability estimate, and for students or clinicians checking a worked Wells Score example against the original published criteria.

Who Should Use This Calculator?

Emergency medicine and internal medicine trainees learning the PE diagnostic workup can use this tool to check worked Wells Score examples against the original criteria. Patients who have had their Wells Score explained by a clinician may use it as an educational reference to understand the terminology involved.

This calculator is strictly for informational and educational purposes and is not a substitute for a physician's clinical judgment. Suspected pulmonary embolism is a potentially life-threatening condition, and any diagnostic workup, including whether further testing or imaging is needed, must be directed by a qualified healthcare provider, never by this tool alone.

What Insights Does the Wells Score Calculator Give You?

Wells Score is the primary result, your total weighted points, based on the criteria you selected.

Three-Tier Probability classifies the score as low, moderate, or high probability of PE, reflecting the original Wells et al. 2000 validation study.

Two-Tier Probability classifies the score as "PE unlikely" or "PE likely" using the simplified threshold adopted in many modern diagnostic algorithms, alongside the three-tier result for comparison.

How to use this Wells Score (PE) calculator

  1. Select Yes or No for Clinical Signs and Symptoms of DVT.
  2. Select Yes or No for PE Is the #1 Diagnosis or Equally Likely.
  3. Select Yes or No for Heart Rate > 100 bpm.
  4. Select Yes or No for Immobilization ≥3 Days or Surgery in Previous 4 Weeks.
  5. Select Yes or No for Previous Objectively Diagnosed PE or DVT.
  6. Select Yes or No for Hemoptysis.
  7. Select Yes or No for Malignancy Treated Within 6 Months, or Palliative.
  8. Review your Wells Score and both probability interpretations, and discuss the result with your physician before deciding on next steps.
Show formula & methodology ↓Show less ↑

Formula & Methodology

The Wells Score sums the following weighted points:

- Clinical signs and symptoms of DVT: 3 points
- PE is the #1 diagnosis or equally likely: 3 points
- Heart rate > 100 bpm: 1.5 points
- Immobilization ≥3 days or surgery in previous 4 weeks: 1.5 points
- Previous objectively diagnosed PE or DVT: 1.5 points
- Hemoptysis: 1 point
- Malignancy treated within 6 months, or palliative: 1 point

Three-tier interpretation: score >6 is high probability, 2-6 is moderate probability, and <2 is low probability.

**Two-tier interpretation:** score >4 is "PE likely," and ≤4 is "PE unlikely."

Worked example: A patient with clinical signs of DVT (3 points) and a heart rate over 100 bpm (1.5 points) scores 3 + 1.5 = 4.5 points total, which is moderate probability on the three-tier scale and "PE likely" on the simplified two-tier scale (since 4.5 exceeds the >4 threshold) per Wells PS, et al. Thromb Haemost. 2000;83:416-420.

Frequently Asked Questions

What is the Wells Score for pulmonary embolism?
The Wells Score is a clinical prediction rule that estimates the pretest probability of pulmonary embolism (PE) based on seven weighted criteria, including clinical signs of DVT, heart rate, immobilization or recent surgery, prior PE or DVT, hemoptysis, and active malignancy. It was developed by Wells PS, et al. and published in Thrombosis and Haemostasis in 2000.
Why do some Wells criteria count for more points than others?
The Wells Score was derived from a regression model where each criterion's weight reflects how strongly it independently predicted PE in the validation cohort. Clinical signs of DVT and PE being the most likely diagnosis carry the most weight (3 points each), while findings like hemoptysis carry less (1 point).
What is the difference between the three-tier and two-tier Wells interpretations?
The original three-tier interpretation classifies patients as low (score under 2), moderate (2 to 6), or high (above 6) probability of PE. The simplified two-tier interpretation, used in many modern diagnostic algorithms, instead classifies patients as 'PE unlikely' (4 or below) or 'PE likely' (above 4).
What happens after a Wells Score is calculated?
The score typically guides the next diagnostic step: a low-probability or 'PE unlikely' result often supports using a D-dimer test to rule out PE without imaging, while a high-probability or 'PE likely' result usually prompts direct imaging such as CT pulmonary angiography. These pathway decisions must be made by a treating clinician.
Can the Wells Score rule out PE by itself?
The Wells Score alone cannot rule in or rule out PE. It is combined with other tests, most commonly D-dimer or imaging, as part of a structured diagnostic algorithm determined by a qualified healthcare provider.
What counts as 'PE is the #1 diagnosis or equally likely'?
This criterion is a clinician's own judgment call about whether, based on the full clinical picture, pulmonary embolism is at least as likely as any other diagnosis being considered, it is inherently subjective and depends on clinical experience rather than an objective test result.
Is the Wells Score used in pregnancy?
The Wells Score has not been specifically validated for use in pregnant patients, who often have separate PE diagnostic algorithms due to physiologic changes like elevated heart rate and baseline D-dimer levels. Pregnant patients with suspected PE should be evaluated using pregnancy-specific pathways determined by their care team.
How is the Wells Score different from the Revised Geneva Score?
Both estimate pretest probability of PE, but the Wells Score includes a subjective clinical gestalt criterion ('PE is the most likely diagnosis'), while the Revised Geneva Score, available on the Revised Geneva Score Calculator, uses only objective clinical variables and adds specific point values for heart rate ranges.
Does immobilization have to be exactly 3 days to count?
The criterion is satisfied by immobilization of at least 3 consecutive days, or by any surgery within the previous 4 weeks, whichever applies, either condition alone is sufficient to score the 1.5 points for that item.
What if I don't know whether I have a DVT?
The 'clinical signs and symptoms of DVT' criterion refers to objective findings such as unilateral leg swelling, tenderness along the deep venous system, or measurable calf circumference difference, which are typically assessed by a clinician during a physical examination rather than self-reported.
Can this calculator replace an emergency medical evaluation for suspected PE?
No, this calculator is strictly for informational and educational purposes. Suspected pulmonary embolism is a potentially life-threatening condition that requires urgent evaluation by a qualified healthcare provider, and this tool must never be used as a substitute for that evaluation or for real-time clinical decision-making.
Are there other tools that pair with the Wells Score in a PE workup?
Yes, the PERC Calculator is often used first in very low-risk patients to determine whether PE can be excluded without any testing, while the Wells Score is used when PE remains a clinical consideration, sometimes alongside bleeding-risk tools like the HAS-BLED Calculator if anticoagulation is being considered.
Also known as
Wells criteria calculatorWells rule for PE calculatorpulmonary embolism probability calculatorWells DVT PE score calculatorPE risk score calculator