Methodology & data sources
Transparency is the core of our E-E-A-T. This page documents where our pricing comes from, how we normalize it across providers, and the exact formulas behind every derived number. The current snapshot date is June 2026.
Where the numbers come from
Every figure is a snapshot of the named vendor's own public pricing page. We track 21 providers across 5 categories. Each vendor page links directly to its source pricing page so you can verify it. We capture list pricing only — negotiated or enterprise rates are private and not shown.
How we normalize each category
| Category | Normalized unit | How we compute it |
|---|---|---|
| Transactional Email APIs | per 1,000 emails | We normalize each vendor's headline plan to a cost per 1,000 emails. Amazon SES is pure pay-as-you-go; the others bundle a monthly fee with an email allowance, so we divide the plan price by its included volume. |
| SMS APIs | per US outbound SMS | Rates shown are the provider's base per-segment price for a US outbound SMS. US carriers add pass-through fees (~$0.003 per message) and most providers rent the phone number (~$1+/month). A2P 10DLC registration is required for US application-to-person traffic. |
| Authentication APIs (per MAU) | per MAU after free tier | We compare the free MAU allowance and the first paid per-MAU rate. Note that advanced features (enterprise SSO, advanced MFA, B2B orgs) are usually paid add-ons that raise the real cost beyond the headline per-MAU rate. |
| Payment Processing APIs | effective rate per online transaction | Rates are for US online (card-not-present) transactions. The effective rate = (percent x amount + fixed fee) / amount. Interchange++ providers (Adyen) pass network fees through at cost, so their effective rate varies with your card mix. International cards and currency conversion add surcharges everywhere. |
| Search APIs | per 1,000 searches / capacity | Usage-based vendors charge per 1,000 search requests plus a per-record fee. Capacity-based vendors charge per node-hour regardless of query count, which can be far cheaper at high query volumes but wasteful at low ones. Open-source engines (Typesense, Meilisearch) are free to self-host. |
The formulas
- Cost per 1,000 emails = plan price ÷ (included emails ÷ 1,000). Amazon SES is pure pay-as-you-go at $0.10 per 1,000.
- Effective payment rate = (percent × amount + fixed fee) ÷ amount. The fixed fee dominates on small charges; the percentage dominates on large ones. Interchange++ providers (Adyen) pass network fees through at cost, so their effective rate varies with card mix and is shown as "varies".
- Authentication cost = base fee + per-MAU rate × max(0, MAU − free-tier MAU). We do not fabricate a per-MAU rate for sales-led tiers (e.g. Auth0 paid plans).
- SMS = the provider's base per-segment rate. US carrier pass-through fees (~$0.003/message), number rental (~$1+/month) and A2P 10DLC registration apply on top and are not part of the headline number.
- Search = per 1,000 search requests + per-record fees (usage-based vendors) or per node-hour (capacity-based vendors). Open-source engines are free to self-host.
Data sources
| Source | Refresh cadence | License |
|---|---|---|
| Vendor published pricing pages (Stripe, Twilio, Auth0, Algolia, etc.) | none | Snapshots of public vendor pricing; trademarks belong to their owners. |
How calculations work in your browser
The calculators run entirely client-side in vanilla JavaScript using the formulas above. We do not store your inputs or send them to a server.
Limitations
API pricing changes frequently and varies by region, plan, contract and card mix. Our figures are estimates for general information and may lag the vendor's current price or contain errors. Always verify against the vendor's own pricing page before relying on a number. Trademarks belong to their respective owners; we are not affiliated with any vendor. See our disclaimer.
Last updated: 2026-06-18