Cheapest gateway as request volume grows
Kong and Zuplo's base/overage knobs above are held fixed — only monthly requests change per row. Unkey uses fixed published step-tiers (not a linear formula), so watch how it stays cheapest almost everywhere except right at the very bottom, where Zuplo's free tier ties it.
| Requests / mo | Unkey | Kong Konnect | Zuplo | Cheapest |
|---|
Why step-tier, base-plus-overage and free-then-steep-overage billing shapes matter
API gateways don't compete on a single sticker price — they compete on how coarsely or finely they meter your request volume. Unkey publishes fixed step-tier plans: free up to 150,000 valid requests/month, then $25 for up to 250,000, $50 for 500,000, $75 for 1 million, $100 for 2 million, $250 for 10 million, $500 for 50 million and $1,000 for 100 million — you simply pick the smallest published tier that covers your volume, with no per-request overage inside a tier. That makes Unkey's bill a step function, not a smooth curve, and it's cheap almost everywhere because each tier bundles a lot of headroom. Kong Konnect's Plus plan flips that: base fee (≈$105/service/mo) + ceil(max(0, requests − 1,000,000) / 1,000,000) × $200, so you always pay the base even at near-zero traffic, but the 1 million-request allowance and moderate per-million overage make it competitive once you're consistently pushing real volume (capped at 10 million requests before Enterprise is required). Zuplo goes a third way: free under 100,000 requests/month, then $25 base + ceil((requests − 100,000) / 100,000) × $100 on Builder — a much steeper overage rate per unit volume than either Unkey or Kong, which pushes Zuplo's own published Enterprise plan (from $1,000/mo) into range once you cross roughly 1-1.1 million requests/month.
There is no vendor whose headline price represents your bill without knowing your actual monthly request volume. A side project or a small internal API well under 100,000 requests/month can run on Unkey or Zuplo's free tiers indefinitely; a startup steadily pushing a few million requests/month will usually find Unkey's step-tiers cheapest; and a team already committed to Kong's ecosystem for its always-on infrastructure features may accept the flat base as the price of never touching a request counter. Run your own request volume through the calculator above instead of trusting a vendor's homepage number.
How this calculator works
The Unkey vs Kong vs Zuplo Cost Calculator compares three API gateway / API-management pricing shapes — Unkey (fixed published step-tiers: free up to 150K, then $25/250K, $50/500K, $75/1M, $100/2M, $250/10M, $500/50M, $1,000/100M requests), Kong Konnect (flat per-service base fee + linear overage per extra million requests) and Zuplo (low base fee + steep per-100K overage) — at your monthly API request volume. Kong's cost is base + ceil(max(0, requests − included) / 1,000,000) × overage rate; Zuplo's is 0 if requests ≤ free tier, else base + ceil((requests − included) / 100,000) × overage rate; Unkey looks up the smallest published tier whose limit covers your request volume. The calculator shows all three totals side by side, then a separate table isolates all three vendors across a range of request volumes, so you can see exactly where each vendor's shape wins or loses.
These are representative pricing shapes based on each vendor's current published self-serve pricing pages (Unkey Pro tiers as published on unkey.com/pricing; Kong Konnect Plus ≈$105/service/month including 1M requests then ≈$200/additional 1M, capped at 10M before Enterprise; Zuplo Free/Builder ≈$25/mo including 100K requests then ≈$100/additional 100K, Enterprise from $1,000/mo), not live vendor quotes — actual pricing varies by contract term, negotiated discounts, number of gateway services/environments and enterprise terms, and all three vendors offer custom enterprise pricing above their published self-serve tiers. Always confirm current pricing directly with the vendor before budgeting.
Frequently asked questions
Is Unkey cheaper than Kong Konnect for an API gateway?
At low-to-mid volume, yes — Unkey's free tier covers 150,000 valid requests/month, and its cheapest paid tier ($25/mo) covers up to 250,000. Kong Konnect's Plus plan has no ongoing free tier and starts around $105/month per gateway service (after a 30-day trial) which includes 1 million requests. So under roughly 1 million requests/month, Unkey is usually cheaper; Kong's flat base only starts paying off once you're consistently using most of that included 1 million-request allowance. At 1M requests/month, Unkey (~$75, its 1M-request tier) still undercuts Kong's $105 base — Kong's tiered step pricing genuinely wins at low volume, not just at the free tier.
Why does Kong Konnect charge a flat base fee instead of per-request?
Kong Konnect's Plus plan bundles gateway infrastructure, a generous 1-million-request allowance and support into one per-service monthly fee (about $105/mo), then charges roughly $200 for each additional 1 million requests up to a 10-million cap before you need Enterprise. That base-plus-overage shape is common for infrastructure-heavy API management platforms: you're paying for a provisioned, always-on gateway service as much as for the requests that flow through it, so the bill doesn't collapse to zero even at near-zero traffic.
When does Zuplo require an Enterprise plan?
Zuplo's Free plan covers up to 100,000 requests/month at $0, and its Builder plan ($25/mo) also includes 100,000 requests but adds an overage rate of about $100 per additional 100,000 requests. That overage rate is steep compared to Unkey or Kong — by around 1-1.1 million requests/month, Builder's running total approaches $1,000/month, which is roughly where Zuplo's Enterprise plan (starting at $1,000/mo on an annual contract, with volume discounts) becomes the more sensible option. In practice, teams above roughly 1 million requests/month should be talking to Zuplo sales rather than staying on Builder's per-100K overage.
Which API gateway is cheapest — Unkey, Kong or Zuplo?
There's no fixed winner because all three meter API requests differently. Unkey uses coarse step-tier plans (pick the smallest published tier that covers your volume, from a free 150K up to $1,000/mo for 100M), which makes it the cheapest option at almost every volume band up to 100 million requests/month. Kong Konnect charges a flat per-service base fee plus linear overage per additional million requests, so it's competitive once your traffic is heavy and steady but never free. Zuplo is cheapest at very low volume (free under 100K) but its per-100K overage rate is the steepest of the three, so it becomes the most expensive option fastest as volume climbs. Run your own monthly request volume through the calculator above instead of assuming a vendor's headline number applies to you.