stepfun — AI API latency & reliability by region

As of September 06, 2026, the stepfun AI API responds in 294 ms p50 (edge, time-to-first-byte) from Asia (Tokyo) — its fastest measured region — with 100% uptime. Slowest is South America (São Paulo) at 653 ms p50.

Is stepfun down right now?

Reachable from all 4 regions

Last successful probe Sep 6, 18:16 UTC · every 5 minutes from 4 region(s)

1 isolated failure(s) in the last 72 hours, the most recent (host probes) visible from only one region (Europe (Germany)). A single-region failure cannot be separated from a problem on that network path, so it is not called an outage. Measured from outside stepfun’s own network, independently of its status page; full log: measured AI API incidents.

Real requests: not measured for stepfun — only the API host is probed here, so errors limited to specific models are invisible to these probes. That is exactly what a status page tends to report, hence the line below.

stepfun publishes no machine-readable status page, so there is nothing to cross-check against.

Edge latency, 24 h
294 ms
p50 from Asia (Tokyo), the fastest region
Uptime, 24 h
100%
1,153 probes across 4 region(s)
Failed probes, 72 h
1
of 3,457 · Europe (Germany)
Reported by stepfun, 72 h
no machine-readable status page

Was stepfun down in the last 3 days?

No. 1 isolated single-region probe failure(s) were recorded, none of which meets the bar for an outage (two or more regions at once).

What stepfun’s own status page reported

stepfun publishes no machine-readable status page, so there is nothing to set against the measurements above.

Is stepfun getting faster or slower?

hourly p50 latencyall probes succeededsome probes failedhalf or more failedno data

stepfun — hourly p50 edge latency (ms) and probe outcomes per region, last 72 hoursSep 4Sep 5Sep 6nowSep 3, 19:00 UTC Europe (Germany): 399 ms US (Central): 411 ms Asia (Tokyo): 283 ms South America (São Paulo): 637 msSep 3, 20:00 UTC Europe (Germany): 402 ms US (Central): 410 ms Asia (Tokyo): 281 ms South America (São Paulo): 636 msSep 3, 21:00 UTC Europe (Germany): 400 ms US (Central): 409 ms Asia (Tokyo): 282 ms South America (São Paulo): 650 msSep 3, 22:00 UTC Europe (Germany): 402 ms US (Central): 412 ms Asia (Tokyo): 280 ms South America (São Paulo): 665 msSep 3, 23:00 UTC Europe (Germany): 433 ms US (Central): 406 ms Asia (Tokyo): 279 ms South America (São Paulo): 649 msSep 4, 00:00 UTC Europe (Germany): 445 ms US (Central): 415 ms Asia (Tokyo): 283 ms South America (São Paulo): 646 msSep 4, 01:00 UTC Europe (Germany): 409 ms US (Central): 432 ms Asia (Tokyo): 286 ms South America (São Paulo): 659 msSep 4, 02:00 UTC Europe (Germany): 442 ms US (Central): 420 ms Asia (Tokyo): 288 ms South America (São Paulo): 667 msSep 4, 03:00 UTC Europe (Germany): 413 ms US (Central): 445 ms Asia (Tokyo): 302 ms South America (São Paulo): 654 msSep 4, 04:00 UTC Europe (Germany): 416 ms US (Central): 408 ms Asia (Tokyo): 301 ms South America (São Paulo): 652 msSep 4, 05:00 UTC Europe (Germany): 452 ms US (Central): 416 ms Asia (Tokyo): 302 ms South America (São Paulo): 671 msSep 4, 06:00 UTC Europe (Germany): 448 ms US (Central): 421 ms Asia (Tokyo): 304 ms South America (São Paulo): 685 msSep 4, 07:00 UTC Europe (Germany): 417 ms US (Central): 430 ms Asia (Tokyo): 303 ms South America (São Paulo): 667 msSep 4, 08:00 UTC Europe (Germany): 451 ms US (Central): 452 ms Asia (Tokyo): 297 ms South America (São Paulo): 664 msSep 4, 09:00 UTC Europe (Germany): 448 ms US (Central): 445 ms Asia (Tokyo): 304 ms South America (São Paulo): 668 msSep 4, 10:00 UTC Europe (Germany): 452 ms US (Central): 430 ms Asia (Tokyo): 288 ms South America (São Paulo): 661 msSep 4, 11:00 UTC Europe (Germany): 452 ms US (Central): 412 ms Asia (Tokyo): 288 ms South America (São Paulo): 666 msSep 4, 12:00 UTC Europe (Germany): 430 ms US (Central): 416 ms Asia (Tokyo): 302 ms South America (São Paulo): 682 msSep 4, 13:00 UTC Europe (Germany): 452 ms US (Central): 430 ms Asia (Tokyo): 692 ms South America (São Paulo): 675 msSep 4, 14:00 UTC Europe (Germany): 1004 ms · 1 of 12 probes failed US (Central): 420 ms Asia (Tokyo): 305 ms South America (São Paulo): 668 msSep 4, 15:00 UTC Europe (Germany): 414 ms US (Central): 438 ms Asia (Tokyo): 300 ms South America (São Paulo): 696 msSep 4, 16:00 UTC Europe (Germany): 450 ms US (Central): 426 ms Asia (Tokyo): 300 ms South America (São Paulo): 653 msSep 4, 17:00 UTC Europe (Germany): 494 ms US (Central): 412 ms Asia (Tokyo): 303 ms South America (São Paulo): 706 msSep 4, 18:00 UTC Europe (Germany): 443 ms US (Central): 428 ms Asia (Tokyo): 294 ms South America (São Paulo): 637 msSep 4, 19:00 UTC Europe (Germany): 403 ms US (Central): 414 ms Asia (Tokyo): 284 ms South America (São Paulo): 630 msSep 4, 20:00 UTC Europe (Germany): 436 ms US (Central): 427 ms Asia (Tokyo): 288 ms South America (São Paulo): 636 msSep 4, 21:00 UTC Europe (Germany): 406 ms US (Central): 437 ms Asia (Tokyo): 287 ms South America (São Paulo): 626 msSep 4, 22:00 UTC Europe (Germany): 405 ms US (Central): 438 ms Asia (Tokyo): 283 ms South America (São Paulo): 628 msSep 4, 23:00 UTC Europe (Germany): 397 ms US (Central): 418 ms Asia (Tokyo): 283 ms South America (São Paulo): 632 msSep 5, 00:00 UTC Europe (Germany): 437 ms US (Central): 413 ms Asia (Tokyo): 289 ms South America (São Paulo): 650 msSep 5, 01:00 UTC Europe (Germany): 409 ms US (Central): 418 ms Asia (Tokyo): 288 ms South America (São Paulo): 648 msSep 5, 02:00 UTC Europe (Germany): 447 ms US (Central): 410 ms Asia (Tokyo): 295 ms South America (São Paulo): 666 msSep 5, 03:00 UTC Europe (Germany): 441 ms US (Central): 410 ms Asia (Tokyo): 293 ms South America (São Paulo): 666 msSep 5, 04:00 UTC Europe (Germany): 445 ms US (Central): 412 ms Asia (Tokyo): 308 ms South America (São Paulo): 695 msSep 5, 05:00 UTC Europe (Germany): 457 ms US (Central): 412 ms Asia (Tokyo): 312 ms South America (São Paulo): 671 msSep 5, 06:00 UTC Europe (Germany): 448 ms US (Central): 417 ms Asia (Tokyo): 307 ms South America (São Paulo): 712 msSep 5, 07:00 UTC Europe (Germany): 415 ms US (Central): 419 ms Asia (Tokyo): 309 ms South America (São Paulo): 678 msSep 5, 08:00 UTC Europe (Germany): 444 ms US (Central): 408 ms Asia (Tokyo): 305 ms South America (São Paulo): 672 msSep 5, 09:00 UTC Europe (Germany): 411 ms US (Central): 423 ms Asia (Tokyo): 294 ms South America (São Paulo): 649 msSep 5, 10:00 UTC Europe (Germany): 437 ms US (Central): 415 ms Asia (Tokyo): 294 ms South America (São Paulo): 693 msSep 5, 11:00 UTC Europe (Germany): 410 ms US (Central): 421 ms Asia (Tokyo): 312 ms South America (São Paulo): 667 msSep 5, 12:00 UTC Europe (Germany): 407 ms US (Central): 409 ms Asia (Tokyo): 311 ms South America (São Paulo): 1564 msSep 5, 13:00 UTC Europe (Germany): 1023 ms US (Central): 454 ms Asia (Tokyo): 308 ms South America (São Paulo): 1551 msSep 5, 14:00 UTC Europe (Germany): 497 ms US (Central): 413 ms Asia (Tokyo): 311 ms South America (São Paulo): 697 msSep 5, 15:00 UTC Europe (Germany): 431 ms US (Central): 416 ms Asia (Tokyo): 315 ms South America (São Paulo): 668 msSep 5, 16:00 UTC Europe (Germany): 495 ms US (Central): 413 ms Asia (Tokyo): 298 ms South America (São Paulo): 693 msSep 5, 17:00 UTC Europe (Germany): 405 ms US (Central): 420 ms Asia (Tokyo): 296 ms South America (São Paulo): 650 msSep 5, 18:00 UTC Europe (Germany): 402 ms US (Central): 423 ms Asia (Tokyo): 296 ms South America (São Paulo): 650 msSep 5, 19:00 UTC Europe (Germany): 398 ms US (Central): 409 ms Asia (Tokyo): 287 ms South America (São Paulo): 649 msSep 5, 20:00 UTC Europe (Germany): 402 ms US (Central): 416 ms Asia (Tokyo): 282 ms South America (São Paulo): 644 msSep 5, 21:00 UTC Europe (Germany): 398 ms US (Central): 420 ms Asia (Tokyo): 283 ms South America (São Paulo): 643 msSep 5, 22:00 UTC Europe (Germany): 406 ms US (Central): 408 ms Asia (Tokyo): 287 ms South America (São Paulo): 641 msSep 5, 23:00 UTC Europe (Germany): 404 ms US (Central): 415 ms Asia (Tokyo): 286 ms South America (São Paulo): 626 msSep 6, 00:00 UTC Europe (Germany): 399 ms US (Central): 412 ms Asia (Tokyo): 288 ms South America (São Paulo): 663 msSep 6, 01:00 UTC Europe (Germany): 404 ms US (Central): 413 ms Asia (Tokyo): 290 ms South America (São Paulo): 642 msSep 6, 02:00 UTC Europe (Germany): 411 ms US (Central): 410 ms Asia (Tokyo): 309 ms South America (São Paulo): 655 msSep 6, 03:00 UTC Europe (Germany): 404 ms US (Central): 414 ms Asia (Tokyo): 304 ms South America (São Paulo): 646 msSep 6, 04:00 UTC Europe (Germany): 451 ms US (Central): 415 ms Asia (Tokyo): 314 ms South America (São Paulo): 657 msSep 6, 05:00 UTC Europe (Germany): 434 ms US (Central): 410 ms Asia (Tokyo): 297 ms South America (São Paulo): 663 msSep 6, 06:00 UTC Europe (Germany): 448 ms US (Central): 408 ms Asia (Tokyo): 310 ms South America (São Paulo): 653 msSep 6, 07:00 UTC Europe (Germany): 442 ms US (Central): 416 ms Asia (Tokyo): 312 ms South America (São Paulo): 688 msSep 6, 08:00 UTC Europe (Germany): 446 ms US (Central): 421 ms Asia (Tokyo): 295 ms South America (São Paulo): 685 msSep 6, 09:00 UTC Europe (Germany): 434 ms US (Central): 415 ms Asia (Tokyo): 308 ms South America (São Paulo): 666 msSep 6, 10:00 UTC Europe (Germany): 426 ms US (Central): 416 ms Asia (Tokyo): 295 ms South America (São Paulo): 652 msSep 6, 11:00 UTC Europe (Germany): 962 ms US (Central): 411 ms Asia (Tokyo): 296 ms South America (São Paulo): 687 msSep 6, 12:00 UTC Europe (Germany): 428 ms US (Central): 414 ms Asia (Tokyo): 310 ms South America (São Paulo): 702 msSep 6, 13:00 UTC Europe (Germany): 442 ms US (Central): 458 ms Asia (Tokyo): 296 ms South America (São Paulo): 660 msSep 6, 14:00 UTC Europe (Germany): 1047 ms US (Central): 490 ms Asia (Tokyo): 306 ms South America (São Paulo): 692 msSep 6, 15:00 UTC Europe (Germany): 462 ms US (Central): 428 ms Asia (Tokyo): 309 ms South America (São Paulo): 676 msSep 6, 16:00 UTC Europe (Germany): 444 ms US (Central): 414 ms Asia (Tokyo): 306 ms South America (São Paulo): 644 msSep 6, 17:00 UTC Europe (Germany): 400 ms US (Central): 418 ms Asia (Tokyo): 287 ms South America (São Paulo): 641 msSep 6, 18:00 UTC Europe (Germany): 435 ms US (Central): 421 ms Asia (Tokyo): 286 ms South America (São Paulo): 670 ms20000Sep 3, 19:00 – Sep 4, 13:00 UTC: all 228 probes succeededSep 4, 14:00 UTC: 1 of 12 probes failed — timeoutSep 4, 15:00 – Sep 6, 18:00 UTC: all 617 probes succeeded20000Sep 3, 19:00 – Sep 6, 18:00 UTC: all 856 probes succeeded20000Sep 3, 19:00 – Sep 6, 18:00 UTC: all 856 probes succeeded20000Sep 3, 19:00 – Sep 6, 18:00 UTC: all 856 probes succeeded
Europe (Germany)now 435 ms · typical 434 msUS (Central)now 421 ms · typical 416 msAsia (Tokyo)now 286 ms · typical 296 msSouth America (São Paulo)now 670 ms · typical 663 ms

One panel per region: the line is the hourly p50 edge latency (shared scale, ms), the strip beneath it is the outcome of that hour’s host probes. Hover any hour for the numbers. Flat is good; a rising line means the endpoint is slowing down from that origin, a gap means no probe succeeded in that hour.

How fast is the stepfun API from each region?

Regionp50 TTFBp95Uptime
Asia (Tokyo)294 ms759 ms100%
Europe (Germany)414 ms1088 ms100%
South America (São Paulo)653 ms1668 ms100%
US (Central)414 ms486 ms100%

Measured from Asia (Tokyo), stepfun responds in 294 ms; from South America (São Paulo) the same API takes 653 ms — 2.2× longer for an identical request. That difference is the network path, not the model, and it applies to every call you make.

What is actually being measured here?

A probe in each region opens a real connection to stepfun’s own API host every five minutes and times DNS resolution, the TCP handshake, the TLS handshake and the first byte of the response. Nothing is routed through a gateway or aggregator, so these figures describe stepfun’s infrastructure rather than a reseller’s. Uptime counts a probe as failed only when the service genuinely fails — a 401 from an unauthenticated probe means the endpoint answered correctly and is counted as up.

What this page does not tell you

These are edge latency numbers: the time before the model begins generating. They say nothing about answer quality, throughput, price, or how long a full completion takes — those depend on the model you call. Edge latency matters because it is unavoidable: it is paid on every request, before a single token exists, and no prompt engineering removes it. Where an API key is available, inference time-to-first-token is measured separately and shown on the region pages with the model named next to the figure. Likewise, an unauthenticated probe cannot see errors that hit only some models or some accounts — the kind a status page usually reports — which is why stepfun’s own reports are shown next to the measurements rather than folded into them.