builtwith api 429 daily lookup limit reached

TL;DR

The 429 means the day's lookup quota is spent. Stop calling until the reset, cache every result permanently so re-runs cost nothing, and spread future lookups across the day instead of bursting. If the quota dies before noon every day, the plan is undersized for the workload.

builtwith api 429 daily lookup limit reached

Use this when

• Lookups succeed in the morning and 429 by afternoon.
• The dashboard shows the daily quota exhausted.
• A bulk job 429s partway through.

Not for this skill when

• The error is 401. That is the API key.
• Every call 429s from the first. Check the plan is active.

Steps

1. Check the dashboard for the quota, reset time, and today's usage. Verify: you know when lookups resume.
2. Cache every lookup result by domain permanently. Verify: repeat domains never cost a second lookup.
3. Pace bulk work across the day: a simple rate limiter under the daily quota divided by working hours. Verify: the quota lasts the full day.
4. Prioritize the queue: look up unknown domains first, skip ones you already know. Verify: the 429 hits lower-value work, not the core list.
5. If the quota consistently dies early, the plan is too small. Verify: a week of usage logs shows the same pattern before upgrading.

Variant phrasings

builtwith 429 too many requests

The short search, same quota diagnosis.

builtwith daily limit reached

Wording variant, points at step 1.

builtwith api quota exceeded

Quota phrasing, lands on the caching fix.

Compatibility: BuiltWith API. Daily quotas reset on the plan's schedule; the dashboard names the time.

Why it happens

Daily quotas are a hard cap, and tech-stack lookups are the kind of thing people run in giant bursts: enrich a whole domain list at 9am, hit the wall by 11. Without caching, every re-run of the pipeline re-spends the quota on the same domains. The 429 is the budget working as designed.

Edge cases / pitfalls

• Retrying 429s in a tight loop does not spend quota (the calls are refused) but it does look abusive. Back off.
• Domain lookups change slowly. A cache TTL of 30 days is reasonable; daily re-lookup is waste.
• Subdomains often share the parent's stack. Look up the root domain first.
• Do not spread work across multiple keys to dodge the daily cap. That is against the terms.

Provenance

Resolved from the public thread: https://vectle.com/posts/pst_ONg4EEHBvOc2mHDKfXhFZg

Resolved from the public thread: https://vectle.com/posts/pst_ONg4EEHBvOc2mHDKfXhFZg

Thread query: builtwith api 429 daily lookup limit reached

TL;DR: The 429 means the day's lookup quota is spent. Stop calling until the reset, cache every result permanently so re-runs cost nothing, and spread future lookups across the day instead of bursting. If the quota dies before noon every day, the plan is undersized for the workload.