Free interactive tools for B2B email
Calculators, generators, validators, and reference lookups for email tracking, deliverability, and sales-engagement decisions. All run client-side. No signup, no upload.
Calculators
ROI Calculator
Compare the 12-month cost of Outsolvi against your current email-tracking tool. Includes per-seat pricing for the realistic feature-tier comparison (not entry-tier-vs-Outsolvi tricks).
MPP Impact
Estimates how many of your reported opens are Apple MPP pre-fetches rather than real human reads. Based on Litmus 58% global Apple Mail market share and the MPP enabled-by-default rate.
Open Rate Checker
Takes your reported open rate and the composition of your recipient list, and estimates what the real human-read rate is after filtering MPP pre-fetches, Gmail proxy duplicates, and corporate-scanner traffic.
CPM Calculator
Computes how much each booked meeting costs at the rep level, given outreach volume, reply rate, and meeting conversion rate. Useful for justifying tool budget and identifying funnel-leak points.
Reply Rate Target
Reverse-engineer the email volume needed to hit a meeting target. Useful for setting weekly send targets that align to monthly meeting quotas.
Sales Cycle
Estimates total sales cycle in business days based on prospect engagement velocity (reply latency, multi-touch density, decision-stakeholder count).
Bounce Rate Calc
Computes bounce rate from total sent and bounced counts. Flags whether you're in healthy territory (<2%), watch zone (2-3%), or sender-reputation-damage zone (>5%).
Volume Planner
Calculates total monthly send volume from rep count, daily target per rep, and working days. Useful for capacity planning.
Yearly Savings
Compares yearly-billed vs monthly-billed cost over 12 months for a SaaS tool. Surfaces the discount and annual saving.
CTR Calculator
Computes CTR (clicks ÷ delivered) and CTOR (clicks ÷ opens). Surfaces which metric to focus on.
List Decay
Models B2B list decay at typical 22-30% per year, broken down per quarter. Surfaces re-verification timing.
Blast Cost
Enter list size and send frequency, see the monthly cost across the major ESPs and a one-to-one sales tool. Surfaces the bulk-vs-sales-mail tradeoff in dollars.
Meeting Rate
Enter your monthly meeting goal and your average reply-to-meeting conversion rate. The tool tells you how many sends and how many replies you need to hit the number.
Deliverability Score
A quick rule-based score (not Google's actual algorithm — nobody has that) that flags the configuration combinations that historically land mail in spam.
Reputation Tier
Maps your sending pattern into one of five reputation tiers (Cold, Building, Established, Trusted, At-Risk) with the specific actions to move up or stop the decline.
Send Cap
Enter domain age, days since warmup started, and current daily volume. The tool returns the safe cap for today and the ramped cap for the next 7 days.
Cooldown Calc
For AEs running one-to-one outreach, knowing when a prospect is safe to touch again is the whole game. This tool gives the cooldown by outcome.
List Size
Backs into the right TAM-source list size from quota, win rate, and meeting-to-opp rate. Stops the 'we need 10,000 accounts' premature-scale impulse.
Email Size
Gmail clips messages above 102KB. Outlook stops syncing attachments above 25MB. This tool tells you whether you'll trip either limit.
Complaint Target
Complaint thresholds are absolute, not relative to history. This tool gives you the per-send and per-month complaint allowance.
Decay Half-Life
Subscribers who haven't opened in N days are deliverability poison. This tool tells you when to suppress.
Generators
SPF Generator
Builds the TXT record for SPF authentication based on which services send mail for your domain. Output is the exact DNS record you paste into your domain registrar.
DMARC Generator
Builds a DMARC v=DMARC1 record with the policy, percentage, and rua/ruf reporting addresses configured for your domain.
UTM Builder
Builds Google Analytics-compatible UTM-tracked URLs for email campaigns. Output is a single URL you paste into your email.
Signature Generator
Creates a B2B-appropriate email signature in both HTML and plain-text format. No image-heavy templates — clean text that renders consistently across mail clients.
Unsubscribe Generator
Builds the unsubscribe link text and mailto fallback for sales-outreach email. Compliant with CAN-SPAM (US) and GDPR-style opt-out conventions.
Plain Text Converter
Takes HTML email body and produces the plain-text alternative version. Properly preserves paragraphs, links (as 'text (url)' notation), and lists.
OOO Generator
Builds a professional out-of-office auto-reply suitable for sales-side communication. Includes optional backup contact and urgency-routing.
Calendar Link Builder
Generates calendar-booking link CTAs in different formats (Calendly, Cal.com, HubSpot) with proper UTM tracking and one-click prefill.
Mailto Builder
Generates a mailto: URL with pre-filled subject, body, CC, and BCC, ready to paste into webpages or messages.
ASCII Dividers
Generates plain-text dividers (--- type) for plain-text emails and signatures. Different visual weights.
BIMI Generator
Produces the `default._bimi` TXT record you publish in DNS so Gmail and Yahoo render your logo next to the sender name in inbox.
MTA-STS
Produces the `.well-known/mta-sts.txt` policy file and the `_mta-sts` DNS TXT record so receiving servers enforce TLS when delivering mail to you.
TLS-RPT
Produces the `_smtp._tls` TXT record. Pair with MTA-STS so you can see what's actually happening at the TLS layer for mail addressed to your domain.
Opt-In Confirm
Produces the confirmation email body and subject for double opt-in flows: subscriber clicks the link to verify, you only add them to the list after confirmation.
1-Click Unsub
Produces both headers (List-Unsubscribe with mailto: and https:, plus List-Unsubscribe-Post: List-Unsubscribe=One-Click) that Gmail and Yahoo require for senders above 5,000/day.
List-Unsub Header
Older sibling of the one-click builder. Produces a List-Unsubscribe header (without the POST extension) for legacy compatibility with older mail clients.
Email Regex
The internet's worst-debated regex. This tool gives you the strict spec version and the practical version most production systems use.
TZ Send Time
Most missed-send-time problems are timezone arithmetic problems. Type your local time, see the recipient's local time across 12 major business zones.
Message-ID
Building an MTA or a programmatic sender? Every outbound message needs a unique Message-ID; this tool gives you a spec-compliant one.
MIME Boundary
The boundary string in multipart MIME must not appear in any encoded part. This tool generates one that's safe.
Cold Template
Generates a personalized cold-outreach template using the AE pattern: specific trigger, why-now relevance, single ask. No sequence-style bulk patterns.
Follow-Up
Follow-ups differ based on the signal. Opened-not-replied calls for a re-state; total silence calls for a fresh angle.
Meeting Request
Asking 'what works?' converts worse than offering two specific times. This template produces the latter.
Renewal Nudge
Renewal nudges fail when they're identical regardless of timing. The 60-day, 30-day, and 14-day touches all need different framing.
Breakup
Breakup emails are useful as the last touch before suppressing. The manipulative versions ('should I close your file?') hurt more than they help.
VM Script
Long voicemails get auto-deleted. 22 seconds is the magic length. This tool generates a script that fits.
LI Connect
LinkedIn connection notes have 300 chars; this tool stays under and includes a real reason (not 'wanted to connect').
Validators
SPF Validator
Parses your SPF record and flags common configuration errors: missing v=spf1 prefix, wrong all-policy, too many DNS lookups (10-lookup limit), missing required includes.
DMARC Validator
Parses your DMARC record and flags syntax issues, missing required directives, and policy-misconfiguration risks.
Email Validator
Bulk-validates email syntax. Doesn't check deliverability (that requires SMTP probes); flags syntactically broken addresses that would bounce immediately.
DKIM Checker
Validates the DKIM TXT record format: v=DKIM1, k= algorithm, p= public key presence.
Headers Parser
Parses raw email headers from a received message. Extracts From, To, Subject, Received hops, Authentication-Results (SPF/DKIM/DMARC), and Message-ID.
PTR Check
Enter your sending IP. The tool returns the PTR record, validates it matches the forward (A) record for the sending hostname, and flags missing or mismatched PTR.
Catch-All
Catch-all domains accept any address; bounce verification looks clean but mail goes to a black hole. This tool flags the pattern.
Disposable
Disposable addresses are a signup-fraud and free-tier-abuse signal. This tool flags them against a maintained list of known throwaway domains.
Role Account
Role accounts get higher complaint rates and lower replies. Sending cold to info@ is a deliverability tax. This tool flags them.
Analyzers
Subject Analyzer
Scores a subject line on length, spam-trigger phrases, ALL CAPS, emoji density, urgency words, and other patterns that affect reply rate in 2026 B2B email.
Preview Analyzer
Analyzes the preview text that appears in inbox snippets after the subject line. Length, repetition with subject, hook quality.
Readability Checker
Computes Flesch reading-ease score for email body text. Higher = easier to read. B2B email sweet spot: 50-70.
Preheader Tester
Paste your subject and the first 200 characters of your email body. The tool shows what the inbox preview will look like in each client and flags the common preheader leak.
Emoji Render
Paste a subject. The tool shows the unicode codepoints and the per-platform emoji image so you see what your recipient actually sees.
Bounce Classifier
The classification rules are buried in RFC 3463 and provider-specific extensions. This tool tells you in plain English: retry, suppress, or investigate.
DMARC RUA Parser
RUA reports arrive as gzipped XML and are unreadable without parsing. This tool extracts the senders, IPs, volumes, and pass/fail rates.
Received Chain
Each Received header is one hop. Parsing them in order shows the message's journey from origin MTA to final delivery — useful for delays and spoofing checks.
Snippet Personalizer
An opening that could apply to any prospect is a tell. This tool scores how prospect-specific your opening actually is.
Converters
CSV Deduplicator
Removes duplicate email addresses from a pasted CSV list. Case-insensitive by default. Optional domain-only mode (one email per domain) for ABM list dedup.
URL Encoder
Encodes special characters in URLs (spaces, ampersands, equals) and decodes encoded URLs back to readable form.
JSON/CSV Converter
Bidirectional JSON ↔ CSV converter for email contact lists. Useful when importing/exporting between tools.
Case Converter
Quick case converter for email-specific copy editing. Sentence case for subject lines (recommended), Title Case for headings, lowercase for casual.
HTML Stripper
Sibling of the Plain Text Converter from batch 1, but designed for the opposite direction: parsing real-world received HTML emails into clean readable text.
MD → Email HTML
Most markdown-to-HTML converters produce CSS that breaks in Outlook desktop. This one produces table-based, inline-styled, Outlook-tested HTML.
Email Normalizer
The Gmail-specific rule (dots don't matter, plus-tags don't matter) means foo.bar+anything@gmail.com is the same as foobar@gmail.com. This tool normalizes.
References
Reply Benchmarks
Reply-rate benchmarks across major B2B segments. Use as the comparison baseline for your own reply rates.
Open Benchmarks
Two-tier open-rate benchmarks: raw pixel-load rates (what most trackers report) and confidence-scored real-read rates (what's actually happening). Differ by 20-40 percentage points typically.
Send Time Optimizer
Recommends the optimal send time for your recipient based on their timezone and category-wide reply-rate research showing Tuesday-Thursday 10am-noon recipient local as the sweet spot.
Warmup Schedule
Recommended 4-week warm-up volume schedule for a new sending domain or IP. Daily targets and weekly checkpoints.
Bounce Benchmarks
Bounce rate ranges across major B2B segments. Use as the baseline for evaluating list health.
Email Client Share
Email client market-share breakdown for 2026. Affects expected MPP-inflated open rate on your list.
Spam Words
Categorized reference of spam trigger words (free, urgent, etc.) and patterns (ALL CAPS, emoji density, $$$) that increase spam scoring.
From Headers
The single most-confused topic in email auth. This page explains both headers, where SPF checks, where DMARC checks, and why a SPF-passing email can still fail DMARC.
MX Lookup
Enter a domain. The tool returns the MX records, the priority of each, the resolving IP for each, and the mail provider behind them (Google Workspace, Microsoft 365, Fastmail, etc.).
ARC Seals
Why a perfectly-authenticated email forwarded through a mailing list often fails DMARC at the final hop — and how ARC fixes it.
Postmaster Checklist
Adding your domain to Google Postmaster Tools gives you ground-truth visibility into how Gmail sees you. This checklist walks the full setup.
SNDS Checklist
If any of your outbound mail hits @outlook.com / @hotmail.com / @live.com / corporate Microsoft 365 tenants, SNDS is the visibility layer you need.
Aliases
you+tag@gmail.com goes to the same inbox as you@gmail.com — but the CRM, the analytics tool, and the deduper all think they're different.
Gmail Operators
Gmail search is powerful when you know the operators. This page is the full reference with practical examples for sales workflows.
Outlook Operators
Outlook search uses Keyword Query Language. This page gives the working operators and the ones that look like they should work but don't.
Protocol Compare
Picking the wrong access protocol gives the wrong tradeoffs (sync, storage, offline, multi-device). This page lays them out side-by-side.
Thread IDs
Threading is a client-side decision based on Message-ID, In-Reply-To, References, and (Gmail) Subject. This page explains all four.
Yahoo CFL
If you send to @yahoo.com / @ymail.com / @aol.com, CFL is the only way to know who marked your mail as spam.
Apple Mail Quirks
Apple Mail makes up 50%+ of B2C and 25%+ of B2B opens. Rendering differences from Gmail/Outlook are real and worth knowing.
Render Quirks
Gmail strips style blocks; Outlook desktop uses Word rendering. Both behaviors require different mitigations.
RBL Explainer
Not all blacklists are equal. Being on Spamhaus ZEN is reputation-killing; being on a no-name list usually isn't. This guide explains.
Spamhaus ZEN
ZEN is the combined zone most mailbox providers query. Each sub-list (SBL, XBL, PBL) gets you blocked for different reasons.
Google FBL
Senders keep asking 'where's Google's FBL?' — the answer is they don't have one in the classic sense, and Postmaster Tools is the substitute.
SSL vs TLS
Email-client configuration UIs still say 'SSL' when they mean 'TLS'. Knowing the difference matters for compliance audits.
STARTTLS
Three SMTP ports, two TLS modes, one extremely common misconfiguration. This guide picks the right combo.
Email Attribution
Attribution decides whether email looks like a cost center or a growth engine. The model choice matters more than the data.
Weekly Checklist
Most deliverability problems are gradual. A 10-minute weekly review catches them at warning-light stage instead of inbox-blackout stage.