Overview

CallMeter brings stress testing, synthetic calls and ongoing SIP monitoring into one service. Its value is greatest for organisations that need evidence about how voice systems behave under load and over time, rather than a basic uptime check. The combination of granular metrics, configurable signaling tests and operational automation gives engineering teams a way to make voice quality part of regular release and incident processes.

Key features

Load tests let teams choose endpoint counts, SIP methods, authentication modes and call duration. SIP message capture with ladder diagrams helps engineers inspect signaling sequences instead of relying only on a pass or fail result. The service measures more than 90 real-time quality metrics for each call, second, endpoint and direction. MOS scoring, jitter tracking and packet-loss tracking make the output useful for diagnosing perceived quality as well as capacity.

Codec coverage includes PCMU, PCMA, G.722, Opus, G.726-32, GSM, Speex, AMR and iLBC for audio, together with H.264, H.265, VP8 and VP9 for video. That is a broad set for mixed voice and video deployments; teams dependent on codecs outside it should verify compatibility before purchase.

Continuous probes operate in caller or callee mode and can run on intervals or cron schedules. Quality thresholds, sliding-window status and webhook notifications support alerting based on sustained degradation rather than a single noisy sample. SIP trunk monitoring and synthetic call tests extend the service from one-off benchmarking to recurring operational checks.

The REST API covers test execution, metric retrieval and probe management. Quality gates for GitHub Actions, GitLab CI and Jenkins let DevOps teams block or flag releases when voice criteria fail. This is a practical advantage for organisations treating telephony changes like other production deployments.

Managed cloud workers are convenient for publicly reachable SIP systems. Docker-based user-owned workers can run inside private networks; signaling and RTP media stay in that customer network, while only aggregated quality metrics leave it. Cloud workers cannot reach infrastructure that is not exposed to the public internet, so private deployments require the user-owned option. CallMeter states that it uses TLS 1.3 in transit, AES-256 at rest, application-level encryption for sensitive credentials, access controls and regular security assessments, and processes personal data under GDPR and CCPA/CPRA.

Pricing

Pricing is on request. Starter, Professional, Business and Enterprise plans are billed monthly or annually, with features, usage limits and service levels varying by plan. That structure can accommodate different operational scales, but it prevents a straightforward cost comparison without a sales discussion. The Enterprise / White-Label plan is billed monthly or yearly, can be cancelled anytime, and adds a multi-tenant, branded, resellable model for providers and channel businesses.

A seven-day free trial requires a valid payment method and converts to a paid subscription unless cancelled before it ends. Teams should schedule an explicit cancellation decision rather than treating the trial as risk-free. No published seat or usage allowances distinguish the paid tiers, so prospective buyers should get those limits and service commitments in writing.

Platforms

CallMeter is delivered through web access and an API, with self-hosted Docker workers for execution inside customer networks. The platform model suits centralised operations teams, while self-hosted workers address environments where SIP signaling and media cannot leave the private network.

Who it's for

Carriers, telecom managers and MSPs can use it to benchmark trunks and customer-facing services. Network engineers and SRE or NOC teams get detailed telemetry and continuous probes for troubleshooting and alerting. DevOps teams benefit from CI/CD quality gates, while procurement teams can use repeatable measurements when evaluating voice infrastructure. It is less suitable for a small user seeking a transparent, fixed-price monitoring tool or for an environment that cannot accommodate the trial’s payment and conversion terms.

Pros and cons

Pros

More than 90 per-call, per-second, per-endpoint and directional metrics provide unusually detailed quality evidence.
Configurable SIP tests and ladder diagrams expose signaling behavior under chosen load conditions.
User-owned workers keep SIP and RTP inside private networks while exporting only aggregated metrics.
API access, webhooks and CI/CD gates connect voice checks to existing engineering workflows.
Broad audio and video codec support covers varied deployments.

Cons

Custom pricing and unpublished tier limits make budgeting and plan selection difficult before speaking with sales.
The seven-day trial requires a payment method and auto-converts unless cancelled.
Cloud workers only reach publicly exposed SIP infrastructure; private systems require Docker workers managed by the customer.

Alternatives

For a wider shortlist, see VoIP Monitoring Software.

Obkio is a freemium, multi-platform option with a 14-day premium trial, up to 10 agents and no credit card requirement.
Dotcom-Monitor suits readers wanting a free tier with up to 25 targets, five-minute monitoring and two locations.
HOMER is the choice for 100% open-source, self-hosted VoIP monitoring, with commercial support available by quote.
ServicePilot VoIP Monitoring offers freemium self-hosted and web monitoring with per-object pricing.
VoIP Spear is a paid alternative with a published Lite plan at 14.95 USD per month.
Exoprise uses a paid credits model.
sip-exporter is free, self-hosted and AGPL-3.0 open source.
Sipfront Beat is a paid self-hosted and web service with a published Starter plan at 89.00 EUR per month.

Verdict

Choose CallMeter when your team needs configurable SIP stress tests, continuous probes, deep quality metrics and private-network execution tied to automation. Its main reason to look elsewhere is commercial uncertainty: pricing and limits require a quote, and the short paid-conversion trial demands careful handling.

	CallMeter	Nectar Diagnostics
Free trial	Yes
Platforms	api, self-hosted, Web	Web
MOS scoring	Yes	Yes
Jitter tracking	Yes	Yes
Packet-loss tracking	Yes	Yes
Synthetic call tests	Yes
SIP trunk monitoring	Yes	Yes

CallMeter vs Nectar Diagnostics

CallMeter

Nectar Diagnostics