# Subject Line Scorer  that picks the winner

Paste up to 5 subject lines. Get transparent sub-scores, real Gmail and Outlook previews, and 5 frame rewrites grounded in what actually books meetings.

Deterministic engine plus Gemini reasoning

[Score my subject lines](https://knowledgenet.ai/tools/subject-line-scorer#scorer-tool)

Score first. Email only to unlock rewrites.30 seconds. Send-ready output.

JD

AK

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RP

Trusted by leading revenue teams. Scores grounded in real spam triggers and inbox truncation, not vibes.

## Live scoring

5 subjects · cold outbound

### Grading

| Subject Line                                       | Score |
|---------------------------------------------------|-------|
| A Quick question about Acme's RevOps stack        | 92    |
| I Saw your Series B — 3 ideas                     | 88    |
| A Free trial inside!! Limited time!               | 28    |

### Gmail mobile preview

Quick question about Acme's RevOps…

Noticed your team is hiring 3 SDRs — wanted to share what's working at…

### Rewrites by frame

- Curiosity
- Specific
- #Trigger event
- Pattern interrupt
- Peer drop

### Audience (optional)

Send context:

- Cold outbound
- Nurture
- Reply bump
- Event invite

Who are you writing to? Calibrates spam, specificity, curiosity, and formatting penalties.

### Persona

- C-suite
- VP / Director
- Manager / IC
- Technical buyer
- Consumer / B2C

### Industry

- SaaS / Tech
- Finance
- Healthcare
- Legal
- E-commerce / D2C
- Manufacturing
- Education
- Nonprofit
- Other

#### Subject lines (1 to 5)

Add another

#### Preheader (optional)

Scored together with the subject so they don't echo each other.

[Score my subject lines](https://knowledgenet.ai/tools/subject-line-scorer#scorer-tool)

## Subjects are the start. Pipeline is the finish.

AI Engage™ writes subject lines, opens, and follow-ups personalized to each account, then routes the replies to a human in the loop.

[See how AI Engage™ works](https://knowledgenet.ai/b2b-prospecting-software)