Overview
Usage limits define how traffic is admitted, billed, and protected in Rewrite. This page explains:- How request and sending quotas work
- PAYG billing model
- Plan-based quotas and upgrades
- What happens at limit boundaries
- Operational best practices
Quota model
Limits are applied to protect platform stability and keep delivery quality high.
Billing model
Billing can follow PAYG pricing or plan-included quota depending on workspace setup.
Rate control
Request pressure is controlled with API rate limiting and retry hints.
Visibility
Usage should be monitored by endpoint, region, and message use case.
Billing modes
- PAYG
- Plans
PAYG is billed per SMS sent.Price:
0.18 per SMS (as configured by Rewrite commercial policy).This model is best for variable traffic or early-stage workloads.Quota dimensions
What happens when you hit limits
- API pressure may return
429with retry hints. - New sends can be blocked once commercial quota is exhausted.
- Behavior depends on billing mode and workspace policy (PAYG vs plan).
Rate-limit headers to read
When rate limited, inspect:X-RateLimit-GlobalX-RateLimit-LimitX-RateLimit-Retry-After
X-RateLimit-Retry-After as the retry hint.
Quota-friendly architecture patterns
Queue sends
Buffer outbound traffic and drain with controlled concurrency.
Use idempotency
Prevent duplicate SMS during retries and partial failures.
Backoff + jitter
Retry transient failures gradually to avoid synchronized spikes.
Segment traffic
Isolate OTP and non-OTP traffic to keep critical flows protected.
Practical policy recommendations
- Set internal soft limits before hard quota boundaries.
- Alert when usage reaches 70%, 85%, and 95% of the window.
- Reserve budget for high-priority use cases (e.g., OTP).
- Auto-throttle lower-priority campaigns during pressure.
- Keep dead-letter queues for sends that exceed policy limits.
Monitoring checklist
- Track
429rate per endpoint and environment. - Track send success, failed, and undelivered ratios by region.
- Track cost per use case (
otp_login,alerts,marketing). - Reconcile internal counters with provider/webhook outcomes.
- Review quota incidents weekly and tune throttling policy.
FAQ
Where do I see current plan values and quotas?
Where do I see current plan values and quotas?
Use the official pricing page: rewritetoday.com/pricing.
Can I combine plan usage and PAYG behavior?
Can I combine plan usage and PAYG behavior?
Commercial behavior depends on workspace configuration. Check your active billing setup in account settings.
What is the safest retry behavior under limit pressure?
What is the safest retry behavior under limit pressure?
Retry only transient failures, respect retry headers, and apply exponential backoff with jitter. See Errors & retries.