GoodSender
the email API for makers and AI agents
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What is GoodSender?
GoodSender is a free email API service designed to eliminate unwanted emails by requiring explicit recipient consent before marketing emails can be sent. Built by Isaac Saldana, co-founder of SendGrid, and a team of SendGrid alumni, it uses a 'Permission Loop' system where recipients must confirm they want to receive communications before senders can reach them. The service supports both transactional emails (like MFA, login, OTP, order confirmations) which don't require consent, and opt-in marketing emails which do require the consent workflow.
Key features include a single HTTP endpoint for sending emails with markdown, HTML, or plain text (which GoodSender renders to email HTML), automatic engagement tracking that monitors opens, clicks, bounces, and complaints per recipient, auto-suppression of unsubscribes and spam complaints across the entire workspace, and automatic re-permission pings after six months of no engagement. The platform offers SDKs for 8 languages (Node, Python, Go, Java, .NET, Ruby, PHP, Rust), domain authentication via DNS records, and API-based consent requests that take approximately 150ms.
GoodSender is specifically built for makers and builders including indie developers, solo founders, AI startups building agentic workflows, small teams, and side projects. It is explicitly not designed for enterprise marketing departments, marketing automation heavy users, or cold outreach teams. The service leverages Laneful's email infrastructure with custom IP lanes and AI agents that monitor traffic health, delivering from a shared high-reputation IP pool.
GoodSender pricing
Pricing model: Freemium
First 100,000 emails per month are completely free ($0), covering both transactional and marketing emails in one bucket with no per-type splits. Beyond the free tier, pricing is $1 per additional 100,000 emails. No subscriptions, no tiers, no credit card required to start. At scale: approximately $9/month at 1 million emails, $99/month at 10 million emails. This pricing is verified as of April 2026. Transactional templates (MFA, New Device, Login, Order Completed, OTP) have no consent gate and are included in the free tier.
GoodSender pros
- 100,000 emails per month completely free
- $1 per 100K emails beyond free tier, no subscriptions
- No credit card required to start
- Built by SendGrid co-founder and alumni team
- Permission Loop prevents spam by design
- Transactional templates require no consent workflow
- Automatic engagement tracking per recipient
- Auto-suppression of unsubscribes workspace-wide
- Markdown input converts to bulletproof email HTML
- SDKs available for 8 programming languages
- Single HTTP endpoint for all email types
- High-reputation shared IP pool for deliverability
- Automatic re-permission after 6 months of inactivity
- Consent requests complete in approximately 150ms
- No spam complaints due to consent requirement
- Cost scales flat at volume ($9 at 1M, $99 at 10M)
- Domain authentication setup in under 10 minutes
GoodSender cons
- No cold email or cold outreach allowed at any volume
- Marketing emails require recipient consent workflow
- Not designed for enterprise marketing departments
- Not suitable for marketing automation power users
- Cannot use purchased email lists
- Dormant recipients automatically drop off after 6 months
- No built-in template designer or visual editor
- Limited to transactional and permission-based marketing only
Frequently asked questions about GoodSender
What is GoodSender?
GoodSender is a free email API service that eliminates unwanted emails by requiring explicit recipient consent before marketing emails can be sent. It provides a single endpoint for sending transactional emails (which don't require consent) and opt-in marketing emails (which require a Permission Loop workflow where recipients confirm before you can mail them).
How much does GoodSender cost?
The first 100,000 emails per month are completely free. Beyond that, it costs $1 per additional 100,000 emails. There are no subscriptions, no tiers, and no credit card required to start. At scale, pricing is approximately $9/month at 1 million emails and $99/month at 10 million emails.
What is the Permission Loop?
The Permission Loop is GoodSender's core mechanism where recipients must confirm they want to receive your mail before you can send to them. You call POST /v1/emails/consent with the recipient's address, GoodSender sends a consent email with approve/reject buttons, and only after the recipient clicks approve can you send emails to that address. If they reject or never respond, sends to that address are discarded.
Do transactional emails require consent?
No, transactional templates do not require consent. Transactional emails like MFA Enrollment, New Device alerts, Login magic-links, Order Completed receipts, and OTP codes are pre-cleared because they're implicitly requested by the recipient's own action. They only fail if the recipient has explicitly clicked reject on consent.
Can I send cold email with GoodSender?
No. GoodSender takes a hard no on cold outreach at any volume. Cold email is considered spam, and the Permission Loop structurally prevents it since purchased lists and cold sequences don't function without recipient consent. The platform is designed specifically to not enable cold outreach workflows.
What programming languages have SDKs?
GoodSender offers SDKs for 8 languages: Node, Python, Go, Java, .NET, Ruby, PHP, and Rust. Each SDK is in its own repository on GitHub and all are generated from the same OpenAPI specification.
How does engagement tracking work?
GoodSender watches every signal—opens, clicks, bounces, and complaints—tracked per recipient and aggregated into a live engagement score. Six months without engagement triggers an automatic re-permission ping. If there's no response, the recipient drops off your list. Unsubscribes and spam complaints are suppressed instantly across the entire workspace.
Who is GoodSender built for?
GoodSender is built for makers and builders including indie developers, solo founders, AI startups building agentic workflows, small teams, and side projects. It's specifically not for enterprise marketing departments, marketing automation power users, or cold outreach teams.
How do I authenticate my domain?
You must add DNS records to verify you own the domain you'll send from. This includes CNAME records for bounces and tracking, DKIM records (dkim1 and dkim2) for cryptographic signing, and a TXT record for DMARC. After adding records, go to your GoodSender dashboard and add your domain. DNS propagation takes a few minutes to up to 48 hours.
Why is GoodSender free at 100K emails?
The Permission Loop removes the abuse surface by construction—purchased lists and cold sequences don't work without consent, so there's virtually no abuse to fight. Without abuse-fighting overhead, the marginal cost of an email drops to just infrastructure (pipe plus metadata). GoodSender passes these savings to users, making the first 100K emails free with a flat cost curve at scale.