Check a templated email against the right recipient and attachment

Compare one fictional draft, resolve recipient and job mismatches, and check selected attachment bytes without sending a message.

Check the assembled draft

A copied service email can greet the right person while still containing another client’s address or job number. Check the recipient, job and attachment as well as the greeting.

Use the email comparison aid to check one fictional draft against an independent reference. It compares one recipient, the greeting, job identifier, version and the contents of two files you select. It does not open a mailbox or send anything. The result shows which supplied inputs agree, which differ and which remain unchecked. You still need to decide what to do with the actual draft.

Start with a reference you did not copy from the draft

In a real workflow, take the reference from the current job and its verified contact: the intended primary email address, complete greeting, job identifier, agreed deliverable version and the file intended for that handoff. If those sources disagree, resolve the disagreement before comparing a draft. Copying both columns from the same draft would only check the draft against itself.

For this exercise, use the fictional reference below. Keep real addresses, messages and client files out of the exercise. You need a browser and a text editor that can save two small plain-text files.

The intended reference is Dana’s JOB-101 handoff at v3. The draft has retained Patrik’s address and JOB-102. A greeting that looks right cannot settle either discrepancy.

1. Compare the prefilled draft without attachments

Open the aid and keep its example values. Click Compare values and attachments without selecting files.

The inspected source predicts these results:

• Recipient: mismatch.
• Greeting: supplied values match.
• Job: mismatch.
• Version: supplied values match.
• Attachment contents: not checked; choose both files.

Keep this draft on hold: the recipient and job disagree, and the attachments have not been compared.

The text comparison removes whitespace at the beginning and end, then compares exact strings. It does not normalize letter case, resolve aliases or determine who owns an address. A blank value on either side is a missing input, not a match. Investigate a difference against the reference rather than changing the reference to make the result agree.

2. Compare actual file contents

Next, check the files themselves. A matching version label cannot tell you which file you selected. Create two small synthetic files in separate folders, both named handoff.txt.

Save this as the reference file:

JOB-101 | v3 | Fictional handoff for Dana

Save this as the draft attachment:

JOB-102 | v3 | Fictional handoff for Patrik

Under Authoritative reference, select the Dana file. Under Draft to check, select the Patrik file. Click the comparison button again. Their contents differ, so the expected attachment result is a mismatch even though the filenames agree. These are practice files, not deliverables or an email to send.

The aid reads the selected files and compares their whole-file SHA-256 fingerprints. It does not rely on filenames or infer what the documents mean. If a file is missing or cannot be read, or the required browser API is unavailable, its contents remain unchecked. Use small files: this implementation reads each selected file in full.

Now make a filesystem copy of the reference file, rename the copy dana-handoff-copy.txt, and select that copy on the draft side. The expected attachment result is a match despite the different filename. Renaming or copying a file preserves its bytes; reopening and resaving it in an editor may change them.

A match says the supplied fingerprints agree. It does not establish that either file is the approved or latest deliverable. Conversely, a mismatch is a reason to inspect the files; it does not explain whether the difference is a wrong client, a changed line ending or something else.

3. Resolve the draft, then compare again

For the fictional exercise, change the draft recipient to [email protected] and the job to JOB-101. Keep the greeting and version as shown, and use the reference file’s renamed copy as the draft attachment.

Changing an input clears the previous result. Run the comparison again after your final selection. The expected outcome is agreement on all five comparisons. If a field is empty, a file is unselected or file reading fails, keep that item unresolved.

These are expected outcomes derived from the inspected source, not a report of a browser trial performed for this article.

4. Make the decision in the actual mail draft

The exercise ends here; send no message. When applying the method to a service-email handoff, the comparison is only one input to a human decision:

1. Return to the current job and verify that your reference still represents the intended recipient and deliverable.
2. Open the actual draft in the mail app. Inspect every To, CC and BCC entry; this aid compares only one primary recipient and does not inspect the mailbox.
3. Read the subject and body for the intended job and version. Open the actual attached file and check it against the intended handoff. Selecting a file in this aid does not attach or replace it in an email.
4. Resolve missing information and disagreements before deciding whether to send, revise or hold the draft. Agreement in the aid is never approval by itself.

If the comparison is unavailable, keep a manual route: compare the fields with the independent reference and open both files to inspect their contents. Record attachment contents as unchecked if you cannot establish what they contain. A matching filename is insufficient.

The aid handles the equality checks without an AI agent. Choosing a valid reference and deciding what to do with the actual message remain your responsibility.

What this guide covers

This is a draft-comparison exercise. It does not establish communication permissions, check conversation history, prevent duplicate follow-ups or guarantee that a message is safe to send. The inspected aid has no mail-send action. That limited observation is not a privacy or security guarantee for a surrounding website, browser extension or later deployment.

The attachment feature depends on browser file reading and Web Crypto. Use the HTTPS edition; do not assume every browser supports the same feature when opening a downloaded HTML file directly. A failed check stays unresolved.

Sources and evidence limits

The comparison behavior and fictional values come from the included aid’s source file, inspected on October 17, 2026. The exercise’s outputs above are predictions from those source files. No measured error reduction, client case or firsthand result is claimed.

The API basis is the W3C Web Cryptography API (First Public Working Draft, April 22, 2025) and File API (Working Draft, September 12, 2026), as supplied and checked for this guide on October 17, 2026. These specifications explain byte reading and digest operations; they do not prove browser compatibility or the correctness of your chosen reference.