SpamAssassin Score Tester

Estimate your email's SpamAssassin-style score by analyzing headers and body content against common spam rules. Results are estimated — real SpamAssassin runs server-side on live email.

How SpamAssassin Scoring Works

SpamAssassin is an open-source anti-spam platform used by millions of mail servers worldwide. It uses a robust scoring framework to evaluate incoming email.

Every test that matches adds (or subtracts) points. By default, if the total score exceeds 5.0, the email is officially flagged as SPAM and will be routed to the Junk folder or rejected entirely.

Positive Score: Bad. Indicates spam-like traits (e.g., all caps subject line, missing Message-ID, HTML only).
Negative Score: Good. Indicates legitimate mail traits (e.g., valid DKIM signature, authenticated DMARC pass).

Our SpamAssassin Score Estimator evaluates a domain against the kinds of rules SpamAssassin applies, showing which signals add points and which subtract them. The lower the score, the more likely mail reaches the inbox.

What is a SpamAssassin Score?

SpamAssassin is a widely deployed open-source spam filter that works by scoring. It applies hundreds of rules to a message, each contributing a positive or negative number, and sums them into a single score.

Positive points indicate spam-like characteristics: blacklist listings, missing authentication, suspicious phrasing, image-heavy layouts. Negative points indicate legitimacy: valid DKIM signatures, aligned SPF, a clean sending history. A message scoring at or above the threshold — 5.0 by default — is classified as spam.

The scoring model matters because it is cumulative. No single rule usually condemns a message. A small authentication problem, a slightly promotional subject line and a shortened link are individually harmless, but together they cross the threshold.

A widely deployed open-source filter that scores rather than blocks
Hundreds of rules each contribute positive or negative points
The default spam threshold is 5.0
Authentication contributes meaningful negative points
Small signals accumulate rather than being judged individually

Why SpamAssassin Scoring Matters

SpamAssassin runs on a very large number of mail servers, particularly in hosting environments, small business mail and self-hosted setups. Even where the major providers use their own systems, the signals SpamAssassin scores are broadly the same ones everyone evaluates.

Understanding the scoring is useful because it is explicit. Unlike the opaque systems at large providers, SpamAssassin tells you exactly which rules fired and what each cost. That makes it a practical diagnostic even for mail destined elsewhere — a message scoring badly here usually has problems that other filters will also notice.

Deployed very widely, especially in hosting and self-hosted mail
The signals it scores are broadly what other filters evaluate
Scoring is explicit, unlike the opaque systems at large providers
A bad score usually indicates problems other filters will also see
Authentication improvements produce measurable negative points

How This Score Estimator Works

The tool evaluates the domain against the signal categories SpamAssassin rules cover.

Validates the domain input against format and SSRF safety checks
Checks SPF, DKIM and DMARC configuration and alignment
Queries blocklists for the domain and its sending infrastructure
Evaluates reverse DNS and HELO consistency
Combines the findings into an estimated score with the contributing factors listed

How to Use the Score Estimator

Enter your sending domain in the input field
Run the estimate to evaluate the signals
Review which factors add points and which subtract them
Address the largest positive contributors first
Re-check after each change to confirm the improvement

Understanding Your Score

Scores and their contributing factors:

Field / Value	Meaning
`Below 0`	Strongly legitimate. Negative points from valid DKIM, aligned SPF and clean reputation outweigh everything else. This is where well-configured senders sit.
`0 to 2`	Normal legitimate mail. Comfortably below the threshold with room for the odd content signal without crossing it.
`2 to 5`	Marginal. Below the default threshold, but some receivers use a lower one, and a single additional signal will push it over.
`5 and above`	Classified as spam at the default threshold. The message is filtered rather than delivered.
`Blacklist points`	Among the heaviest positive contributors. A single listing on a widely used blocklist can add several points on its own.
`Missing authentication`	Absent SPF, DKIM or DMARC removes the negative points a well-configured sender earns, which matters as much as any positive rule.
`Content signals`	Promotional phrasing, excessive capitalisation, image-heavy layouts and shortened links each add small amounts that accumulate.

Common Problems & How to Fix Them

Blacklist rules carry some of the heaviest weights, and no content improvement compensates for them.

Identify which list, find why you were listed, fix the cause, and request delisting. This is always the first thing to address — everything else is marginal by comparison.

Valid DKIM signatures and aligned SPF earn negative points that offset the small positive contributions ordinary mail accumulates. Without them you start from zero rather than from below it.

Configure SPF, DKIM and DMARC correctly and ensure alignment with your From domain. This is the highest-value change available to most senders, and it helps at every filter rather than only SpamAssassin.

Excessive capitalisation, multiple exclamation marks, urgent phrasing, a high image-to-text ratio and shortened links each add small amounts.

None is decisive alone, but they compound. Write in a normal register, maintain a reasonable text-to-image balance, use full URLs rather than shorteners, and avoid the phrasing patterns that promotional mail overuses.

SpamAssassin is only one filter, and the large providers use their own systems weighted heavily towards engagement and sending reputation.

Check Google Postmaster Tools and Microsoft SNDS for provider-specific reputation data. A good SpamAssassin score with poor placement at Gmail usually points to engagement rather than configuration.

Content rules fire differently depending on the message, so scores naturally vary across a campaign.

Focus on the structural factors that apply to every message — authentication, reverse DNS, blacklist status — since those move the baseline. Content tuning only matters once the baseline is as low as it can be.

Best Practices

Fix blacklist listings first, since they carry the heaviest weights
Configure SPF, DKIM and DMARC to earn negative points
Ensure authentication aligns with your From domain
Set reverse DNS matching the HELO hostname
Maintain a reasonable text-to-image balance
Use full URLs rather than link shorteners
Re-check after each change rather than making several at once

Security Recommendations

Investigate a blacklist listing as a possible compromise rather than only as a deliverability problem
Enforce DMARC so spoofed mail using your domain does not affect your reputation
Audit every third-party sender in your SPF record, as each contributes to how your domain scores
Monitor DMARC reports for unfamiliar sending sources
Secure forms and endpoints that could be abused to send mail from your infrastructure
Remember a low score does not indicate the mail is legitimate, only that it does not look like spam

Frequently Asked Questions

Below zero is ideal, and 0 to 2 is normal for legitimate mail. The default spam threshold is 5.0, but some receivers set it lower, so scores in the 2 to 5 range are riskier than the default threshold suggests.

Hundreds of rules each contribute a positive or negative number, and the results are summed. Spam-like characteristics add points; legitimacy signals such as valid DKIM subtract them. No single rule usually decides the outcome.

Blacklist listings add the most points, and authentication earns the most negative points. Content signals are individually small, though they accumulate. Fix listings and authentication before tuning content.

Yes, and it is the goal. Valid DKIM signatures, aligned SPF, DMARC and a clean sending reputation all contribute negative points that can outweigh the small positive contributions ordinary mail accumulates.

No. SpamAssassin is one filter among many, and the large providers use their own systems weighted heavily towards engagement and sending reputation. A good score is necessary rather than sufficient.

Content rules fire differently depending on the message, so variation across a campaign is normal. The structural factors — authentication, reverse DNS, blacklist status — are what set the baseline that content then moves around.

No single word does. Individual content rules carry small weights and only matter when they accumulate. The larger effects come from authentication and reputation, not vocabulary.