--- title: "Best SPF Flattening Tools Compared for 2026 | AutoSPF" description: "Compare the best SPF flattening tools of 2026 — AutoSPF, PowerDMARC, Valimail and more. See rescan speed, macros, pricing, and which one fits your setup." image: "https://autospf.com/images/og-default.png" canonical: "https://autospf.com/spf-flattening/best-spf-flattening-tools/" --- # Best SPF flattening tools The best SPF flattening tools are AutoSPF (dedicated flattening plus macros, 15-minute rescans, from $37/mo), PowerDMARC and Valimail for full DMARC platforms, and DMARCDuty for a free tier. AutoSPF is the top automated pick for keeping SPF under the 10-lookup limit. If your SPF record has crept past the RFC 7208 10-lookup limit, the fix is to flatten it: resolve every `include:`, `a`, `mx`, and `redirect` mechanism down to the underlying `ip4:` and `ip6:` addresses that consume zero lookups. The right tool does that automatically, keeps the record fresh as vendor IPs change, and never pushes you over the limit again. This guide compares the best SPF flattening tools available today, explains how to choose between them, and recommends where each one fits. Full disclosure: AutoSPF is one of the tools compared below, and this page is published by AutoSPF. We have aimed to be fair about every product. If any detail is inaccurate, [contact us](/contact-us/) and we will correct it. For the fundamentals behind all of this, see the pillar guide on [SPF flattening](/spf-flattening/). ## What makes a good SPF flattening tool? Manually flattening a record works exactly once. Google, Microsoft, and SendGrid all rotate their sending IP ranges periodically, and the moment they do, a static hand-flattened record goes stale and silently de-authorizes legitimate senders. That is the single most common cause of surprise SPF failures. A good tool removes that risk. When you evaluate options, weigh these capabilities: - **Automatic rescans.** The tool should re-resolve includes and re-publish on a schedule. Shorter intervals mean a smaller window in which a vendor IP change can break authentication. Look for 15 minutes or less. - **Flattening, macros, or both.** Traditional flattening writes resolved IPs into your DNS. SPF macros (RFC 7208 §7) delegate per-query resolution to a managed service and bypass the 10-lookup cap entirely. The strongest tools offer both so you can pick per domain — see [SPF flattening vs macros](/spf-macros-vs-flattening/) for the trade-offs. - **De-duplication and size control.** Overlapping CIDRs across includes should be merged so the record stays compact and under the 255-character-per-string TXT limit. - **Vendor-agnostic setup.** The tool should work with any DNS provider (Cloudflare, Route 53, Azure DNS, GoDaddy) and any email platform without forcing you to migrate infrastructure. - **DNS rollback and change logs.** If a change breaks something, you need to revert to a known-good record and show an audit trail. - **Enterprise controls where relevant.** SLAs, DPAs, SSO/SAML, RBAC, and SOC 2 attestation matter for regulated teams and MSPs managing many domains. ## Comparison of the best SPF flattening tools | Tool | Approach | SPF-dedicated | Rescan | Macros | Enterprise SLA | Starting price | | ------------------------- | ------------------- | ------------------ | ---------- | -------- | -------------- | ---------------- | | **AutoSPF** | Flattening + macros | Yes | 15 min | Premium+ | 99.99% | $37/mo | | PowerDMARC PowerSPF | Hosted macros | No (full platform) | Varies | Yes | Check vendor | Custom quote | | MxToolbox Delivery Center | Flattening | No (diagnostics) | Continuous | No | Check vendor | Custom quote | | DMARCLY Safe SPF | Hosted flattening | No (DMARC+SPF) | Varies | No | No | \~$17.99/mo | | Redsift OnDMARC | Dynamic SPF | No (full platform) | Real-time | No | Check vendor | Enterprise quote | | Valimail Instant SPF | Patented macros | No (full platform) | Real-time | Yes | Check vendor | Enterprise quote | | EasyDMARC EasySPF | Dynamic flattening | No (full platform) | Varies | No | Check vendor | \~$35.99/mo | | DMARCDuty DynamicSPF | Dynamic flattening | Yes | Varies | No | No | Free tier | _Pricing reflects published vendor and G2 data and can change; confirm current figures with each vendor._ ### AutoSPF — best automated, dedicated option AutoSPF is built for one job: keeping your SPF record valid and under the 10-lookup limit through both automatic flattening and SPF macros. Because SPF is the whole product rather than one feature inside a DMARC suite, setup is fast and pricing reflects only the problem you are solving. It is built by DuoCircle LLC and serves more than 2,000 businesses. Setup is a copy-paste-replace workflow that takes under 60 seconds: you add a single `include:` pointing at AutoSPF’s server, and the platform takes over. From there, AutoSPF **rescans upstream vendor IP ranges every 15 minutes and automatically re-publishes an optimized, de-duplicated record** when those IPs change — with zero manual intervention. Crucially, it resolves to the exact same IPs the upstream includes resolve to, so you get no over-authorization and no broadening of who can send as your domain. Premium and Enterprise plans add SPF macros for unlimited includes, plus 99.99% uptime SLAs, DPAs, SSO/SAML, RBAC, audit logs, and DNS rollback. AutoSPF sits alongside your existing DMARC stack; you never rip anything out. **Best for:** organizations of any size that want SPF solved reliably without adopting a full platform — and MSPs and enterprises needing compliance documentation and SSO. ### PowerDMARC PowerSPF A full email-authentication platform (DMARC, SPF, DKIM, BIMI, MTA-STS, TLS-RPT) whose PowerSPF module uses hosted macros to stay under the lookup limit. Best for teams that want everything managed from one dashboard under one vendor contract. The trade-off: if all you need is SPF fixed, you are paying for a whole platform, and resolution depends on PowerDMARC’s DNS being available at query time. ### MxToolbox Delivery Center The long-standing DNS diagnostics platform, with SPF flattening bundled into its paid Delivery Center tier. Its free MX, blacklist, SMTP, and DNS lookup tools are industry staples. Best for IT admins who want a Swiss Army knife for diagnostics with flattening as one capability. It does not offer macro support, and the free tier is diagnostics only. ### DMARCLY Safe SPF A budget-friendly DMARC and SPF platform with a beginner-friendly interface and Safe SPF flattening. Best for small teams with simpler sending stacks. Because it uses traditional flattening without macros, very complex setups risk exceeding the TXT character limit, and enterprise SLA options are limited. ### Redsift OnDMARC (Dynamic SPF) An enterprise email-security platform whose Dynamic SPF maintains a single optimized record that auto-updates in real time, with macro support for legacy compatibility. Best for large enterprises wanting SPF folded into broader brand protection and compliance. If SPF is your only concern, the full-platform cost is heavy. ### Valimail Instant SPF A patented, macro-based approach that generates SPF responses per query in milliseconds, bypassing the lookup limit entirely. Now part of DigiCert. Best for enterprises with strict compliance needs that want a differentiated, zero-DNS-maintenance approach. The patented resolver creates vendor lock-in, and pricing is enterprise-tier. ### EasyDMARC EasySPF A guided DMARC platform whose EasySPF replaces a complex record with a single managed include, with smart DNS scanning and one-click Cloudflare setup. Best for teams new to authentication who value education-first onboarding. Advanced users may find the guided UI slower than a dedicated tool, and rescan cadence trails AutoSPF’s 15-minute cycle. ### DMARCDuty DynamicSPF A lightweight service with a genuinely free tier for automatic flattening — no self-hosting required. Best for budget-conscious teams or individuals who need basic flattening. It lacks enterprise features such as SLAs, RBAC, and audit logs, so organizations tend to outgrow it. ### Free and self-hosted options Beyond DMARCDuty’s free tier, `cfspf` suits Cloudflare users, and self-hosted scripts like `spfflatten` or the `spf-tools` suite give you full control if you are comfortable running cron jobs and wiring up your own rate limiting. Free tools are great for getting started, but they typically lack the automated rescans, uptime guarantees, and support that production email needs. ## How to choose the right tool Map your needs against three questions before shortlisting: 1. **Is the 10-lookup limit your only problem?** If DMARC reporting is already handled, a dedicated SPF tool (AutoSPF, DMARCDuty) deploys faster and costs far less than a full platform. If you need SPF, DKIM, DMARC, and BIMI together, a platform makes sense. 2. **How many domains and senders?** Under five domains with a simple stack can use a budget or free tool. Multi-domain enterprises and MSPs need centralized management, RBAC, and predictable per-domain pricing. 3. **Do you need compliance artifacts?** If SLAs, DPAs, SSO/SAML, or SOC 2 attestation are requirements, your shortlist narrows to enterprise tiers. Whichever tool you choose, start by auditing your current record with the [SPF Checker](/tools/spf-checker/) to see exactly how many lookups you are using and where you stand against the limit. If you want to see the mechanics behind the fix, read [how to flatten an SPF record](/spf-flattening/how-to-flatten-an-spf-record/), and if you are worried about side effects, check [does SPF flattening affect DKIM & DMARC](/spf-flattening/does-spf-flattening-affect-dkim-dmarc/). ## Frequently Asked Questions ### What is the best free SPF flattening tool? For a hands-off free option, DMARCDuty offers automatic flattening with no self-hosting, and `cfspf` works well inside the Cloudflare ecosystem. Free tools are fine for getting started, but they usually lack the frequent automatic rescans, uptime guarantees, and support that business-critical email needs. For production use, a paid tool that rescans every 15 minutes is worth the modest cost. ### Which SPF flattening tool is best for enterprises? Enterprises should prioritize signed SLAs, DPAs, SSO/SAML, RBAC, audit logs, and DNS rollback. AutoSPF’s Enterprise tier provides all of these with a 99.99% uptime SLA while keeping SPF independent of your DMARC stack. Redsift OnDMARC and Valimail are strong alternatives when you want SPF bundled into a broader email-security platform. ### Do I still need a flattening tool if I already have DMARC? Yes. DMARC only passes when SPF or DKIM passes and aligns with the From domain. If your SPF record exceeds 10 lookups it returns a `PermError`, and SPF fails for every message. Unless DKIM alone is passing and aligned, that broken SPF record blocks your path to `p=quarantine` or `p=reject`. A valid, flattened SPF record is a prerequisite for DMARC enforcement. ### How often should an SPF flattening tool rescan my record? Because vendors rotate sending IPs without notice, the rescan interval determines how long a stale record can silently break authentication. A 15-minute cycle, as AutoSPF uses, gives the best balance of freshness and stability. If you flatten manually instead, audit and update the record at least monthly — weekly is safer. ### Does flattening over-authorize my SPF record? It should not, if the tool resolves includes to the exact IPs those includes resolve to. AutoSPF does precisely this — it never adds broader ranges than your upstream vendors publish, so you avoid authorizing senders you did not intend. Poorly built or manual flattening that collapses CIDRs too aggressively is where over-authorization risk creeps in. Rated 5/5 on G2 · Trusted since 2018 ## Trusted by 50,000+ domains ### "AutoSPF Flattens SPF Records Seamlessly & Keeps Changes Logged - I am quite pleased with the product" > It does what it promises to do, and does it very well. I appreciate that it keeps a log of changes made, which prevents many mistakes. A client's SPF record would have way too many lookups, but AutoSPF makes that problem go away. The length of the SPF record is typically not the issue; it's the amount of lookups in the record that are. AutoSPF "flattens" the record, automatically expanding the defined lookups to IP addresses or ranges. And it auto-updates the record when the un-flattened lookups change. PJ Peter J. President · Small-Business (50 or fewer emp.) ### "Helped us go beyond capacity" > AutoSPF did exactly as described, it helped us get past our 10 lookup limit. Afterwards, we hit another limit regarding overall capacity and when contacted, they quickly provided us with a new solution to eliminate capacity issues entirely going forward, so now we can add as many SPF records as needed. They also provided us with a personalized support video explaining their new method in its entirety using our instance as the example. VU Verified User Financial Services · Mid-Market (51-1000 emp.) ### "Great service and great support" > AutoSPF was easy to initially set up on our own and a great cost effective entry into spf flattening. Needed our first support assistance today and got great response including a video demonstrating the issue I was trying to solve, a quick fix, and more detailed followup. GF Greg F. Mid-Market (51-1000 emp.) 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