Software · head to head
Rollbar vs Fluentd
The short version
- Each has a real cost: Rollbar the free plan allows 5,000 occurrences a month with 30 day retention; Fluentd fluentd needs more than 60 MB of memory at runtime, against roughly 450 KB for Fluent Bit
- They diverge on capability: Rollbar covers Error tracking, Fluentd covers Log collection.
Where they differ
Only the attributes on which Rollbar and Fluentd actually diverge.
Identical on both: starting price (Free), free tier (Yes), platforms (Web, Api), user rating (Not yet rated), category (Unknown).
What each one covers
Drawn from each product's published feature list. An absence here means we hold no record of it - not that the product lacks it.
Only in Rollbar
- Error tracking
- Real-time alerts
- Error grouping
- Source maps
Only in Fluentd
- Log collection
- Data parsing
- Filtering and buffering
- Event routing
Both cover
- API
- Webhooks
- REST
- Web support
- Api support
What people use each for
The jobs each tool is most often brought in to do.
Rollbar
- Tracking application errors and exceptions across deploymentsnot Fluentd
- Grouping and alerting on production error occurrencesnot Fluentd
Fluentd
- Unified log collection and routing from many sources to many destinationsnot Rollbar
- Parsing and transforming log records before forwardingnot Rollbar
- Aggregating logs from containers into Elasticsearch, S3 or a SIEMnot Rollbar
Where each one falls short
Documented limitations, not opinions. Every one is a constraint you would hit in normal use.
Rollbar
- The free plan allows 5,000 occurrences a month with 30 day retention
- Retention is a paid ladder rather than a setting, at up to 90 days on Essentials and up to 180 on Advanced
- Advanced alerting, the RQL analytics query language and SCIM provisioning are excluded from the free plan
- Enterprise requires a $4M annual plan minimum
- No price is published for Essentials or Advanced, so only the free tier has a visible cost
Fluentd
- Fluentd needs more than 60 MB of memory at runtime, against roughly 450 KB for Fluent Bit
- Fluentd is built as a Ruby gem and depends on other gems, so a Ruby runtime is required
- Its capability comes from over 1,000 external plugins rather than built in functionality, so each added input or output is a separate dependency
- The Fluent Bit documentation states that cloud providers have switched from Fluentd to Fluent Bit for performance and compatibility and calls Fluent Bit the next generation solution
Pricing, plan by plan
Rollbar
Free- FreeFree
- Error tracking
- Real-time alerts
- Error grouping
Fluentd
Free- FreeFree
- Log collection
- Data parsing
- Filtering and buffering
Which should you pick?
Choose Rollbar if
- You need error tracking.
- You want to start without paying.
- You work on Web, Api.
- You also want real-time alerts.
Choose Fluentd if
- You need log collection.
- You want to start without paying.
- You work on Web, Api.
- You also want data parsing.
Questions people ask
- Is Rollbar or Fluentd better?
- Neither clearly leads. Rollbar starts at Free and Fluentd at Free, and user ratings are close enough to be indistinguishable. Choose on capability and platform support.
- Which is cheaper, Rollbar or Fluentd?
- Rollbar starts at Free and Fluentd at Free.
- Does Rollbar or Fluentd run on more platforms?
- Both run on Web, Api, so platform support will not decide this one for you.
- Can I use Rollbar for free?
- Both have a free tier, so you can try either at no cost before committing.
- What is Rollbar best used for?
- Rollbar is most often used for tracking application errors and exceptions across deployments, grouping and alerting on production error occurrences. Of those, tracking application errors and exceptions across deployments and grouping and alerting on production error occurrences are not what Fluentd is typically brought in for.
- What can Rollbar do that Fluentd cannot?
- Rollbar covers Error tracking, Real-time alerts, Error grouping, Source maps. Fluentd covers Log collection, Data parsing, Filtering and buffering, Event routing. Both handle API, Webhooks, REST, Web support.


